[armhf] roll buildstage back to alpine 3.12

[armhf] revert linuxserver#125 and use py3-cryptography alpine package, avoiding rust-lang/cargo#9187

closes linuxserver#127

Dockerfile.armhf

@@ -1,5 +1,5 @@
 # Buildstage
-FROM ghcr.io/linuxserver/baseimage-alpine:arm32v7-3.13 as buildstage
+FROM ghcr.io/linuxserver/baseimage-alpine:arm32v7-3.12 as buildstage
 
 # set NZBGET version
 ARG NZBGET_RELEASE
@@ -65,14 +65,12 @@ LABEL maintainer="thelamer"
 RUN \
  echo "**** install build packages ****" && \
  apk add --no-cache --upgrade --virtual=build-dependencies \
-	cargo \
-	g++ \
+	gcc \
 	libc-dev \
-	libffi-dev \
 	libxml2-dev \
 	libxslt-dev \
 	make \
-	openssl-dev \
+	py3-cryptography \
 	python3-dev && \
  echo "**** install packages ****" && \
  apk add --no-cache \
@@ -100,7 +98,6 @@ RUN \
 	build-dependencies && \
  rm -rf \
 	/root/.cache \
-	/root/.cargo \
 	/tmp/*
 
 # add local files and files from buildstage

readme-vars.yml

@@ -70,6 +70,7 @@ app_setup_block: |
 
 # changelog
 changelogs:
+  - { date: "08.04.21:", desc: "Revert buildstage to alpine 3.12 and fix py cryptography on armhf." }
   - { date: "23.01.21:", desc: "Rebasing to alpine 3.13." }
   - { date: "26.10.20:", desc: "Fix python dependencies." }
   - { date: "24.08.20:", desc: "Fix ignored umask environment variable." }