SQLITE: fix Write-Ahead Log option and file permissions

sqlite Write-Ahead Log option and file permissions are set on a file named "ironic.db",
but Ironic file used by Ironic is "ironic.sqlite" as bellow.

ironic-config/ironic.conf.j2:
connection = sqlite:////var/lib/ironic/ironic.sqlite

fix #549

Signed-off-by: LALLAU Bertrand <bertrand.lallau@gmail.com>

Dockerfile

@@ -64,7 +64,7 @@ COPY ironic-config/apache2-ipxe.conf.j2 /etc/httpd-ipxe.conf.j2
 
 # DATABASE
 RUN mkdir -p /var/lib/ironic && \
-  sqlite3 /var/lib/ironic/ironic.db "pragma journal_mode=wal" && \
+  sqlite3 /var/lib/ironic/ironic.sqlite "pragma journal_mode=wal" && \
   dnf remove -y sqlite
 
 # configure non-root user and set relevant permissions