build: improve comments in firecfg.config

Remove the space after `#` for commented code and use `#` instead of `-`
for comments at the end of the line.

Commands used to search and replace:

    $ f=src/firecfg/firecfg.config; printf '%s\n' "$(sed -E \
      -e '3,9999s/^# /#/' \
      -e '3,9999s/^#([^ ]+) --? /#\1 # /' \
      "$f")" >"$f"

src/firecfg/firecfg.config

@@ -51,7 +51,7 @@ ani-cli
 anydesk
 apktool
 apostrophe
-# ar - disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
+#ar # disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
 arch-audit
 archaudit-report
 ardour4
@@ -63,9 +63,9 @@ arm
 artha
 assogiate
 asunder
-# atom
-# atom-beta
-# atool - disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
+#atom
+#atom-beta
+#atool # disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
 atril
 atril-previewer
 atril-thumbnailer
@@ -112,10 +112,10 @@ brave-browser-beta
 brave-browser-dev
 brave-browser-nightly
 brave-browser-stable
-# bunzip2 - disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
-# bzcat - disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
+#bunzip2 # disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
+#bzcat # disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
 bzflag
-# bzip2 - disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
+#bzip2 # disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
 cachy-browser
 calibre
 calligra
@@ -236,14 +236,14 @@ enpass
 eog
 eom
 ephemeral
-#epiphany - see #2995
+#epiphany # see #2995
 equalx
 et
 etr
 evince
 evince-previewer
 evince-thumbnailer
-#evolution - see #3647
+#evolution # see #3647
 exfalso
 exiftool
 falkon
@@ -319,7 +319,7 @@ git-cola
 gitg
 github-desktop
 gitter
-# gjs -- https://github.com/netblue30/firejail/issues/3333#issuecomment-612601102
+#gjs # https://github.com/netblue30/firejail/issues/3333#issuecomment-612601102
 gl-117
 glaxium
 globaltime
@@ -440,7 +440,7 @@ karbon
 kate
 kazam
 kcalc
-# kdeinit4
+#kdeinit4
 kdenlive
 kdiff3
 keepass
@@ -450,7 +450,7 @@ keepassx2
 keepassxc
 keepassxc-cli
 keepassxc-proxy
-# kfind
+#kfind
 kget
 kid3
 kid3-cli
@@ -467,15 +467,15 @@ kodi
 konversation
 kopete
 krita
-# krunner
+#krunner
 ktorrent
 ktouch
 kube
-# kwin_x11
+#kwin_x11
 kwrite
 lbry-viewer
 leafpad
-# less - breaks man
+#less # breaks man
 librecad
 libreoffice
 librewolf
@@ -500,12 +500,12 @@ lollypop
 lomath
 loweb
 lowriter
-# lrunzip - disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
-# lrz - disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
-# lrzcat - disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
-# lrzip - disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
-# lrztar - disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
-# lrzuntar - disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
+#lrunzip # disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
+#lrz # disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
+#lrzcat # disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
+#lrzip # disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
+#lrztar # disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
+#lrzuntar # disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
 luminance-hdr
 lximage-qt
 lxmusic
@@ -697,9 +697,9 @@ profanity
 psi
 psi-plus
 pybitmessage
-# pycharm-community - FB note: may enable later
-# pycharm-professional
-# pzstd - disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
+#pycharm-community # FB note: may enable later
+#pycharm-professional
+#pzstd # disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
 qbittorrent
 qcomicbook
 qemu-launcher
@@ -787,7 +787,7 @@ spectral
 spotify
 sqlitebrowser
 ssh
-# ssh-agent - problems on Arch with Fish shell (#1568)
+#ssh-agent # problems on Arch with Fish shell (#1568)
 standardnotes-desktop
 start-tor-browser
 steam
@@ -888,7 +888,7 @@ uget-gtk
 unbound
 unf
 unknown-horizons
-# unzstd - disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
+#unzstd # disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
 url-eater
 utox
 uudeview
@@ -901,10 +901,10 @@ vivaldi-beta
 vivaldi-snapshot
 vivaldi-stable
 vlc
-#vmplayer - unable to install kernel modules (see #5861)
-#vmware - unable to install kernel modules (see #5861)
-#vmware-player - unable to install kernel modules (see #5861)
-#vmware-workstation - unable to install kernel modules (see #5861)
+#vmplayer # unable to install kernel modules (see #5861)
+#vmware # unable to install kernel modules (see #5861)
+#vmware-player # unable to install kernel modules (see #5861)
+#vmware-workstation # unable to install kernel modules (see #5861)
 vscodium
 vulturesclaw
 vultureseye
@@ -979,10 +979,10 @@ zeal
 zim
 zlib-flate
 zoom
-# zpaq - disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
-# zstd - disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
-# zstdcat - disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
-# zstdgrep - disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
-# zstdless - disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
-# zstdmt - disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
+#zpaq # disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
+#zstd # disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
+#zstdcat # disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
+#zstdgrep # disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
+#zstdless # disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
+#zstdmt # disable until we fix CLI archivers for makepkg on Arch (see discussion in #3095)
 zulip