control: fix removed packages on debian installer (linuxmint)

The debian installer requires libavcodec60 as a dependency, which is
already included in linuxmint through libavcodec-extra60, creating a
package conflict.
Changes to fix this :
- also accept libavcodec-extra as a dependency as it includes libavcodec

GitLab: #1937
Change-Id: Ia3ab39e6d8bd233414c607ab70fd70af629595b0

extras/packaging/gnu-linux/rules/debian-qt/control

@@ -261,7 +261,7 @@ Build-Depends: debhelper (>= 9),
                gperf,
                khronos-api,
 # libasound2-dev [linux-any],
-               libavcodec-dev (>= 7:3.4.8~),
+               libavcodec-dev (>= 7:3.4.8~) | libavcodec-extra-dev (>= 7:3.4.8~),
                libavformat-dev (>= 7:3.4.8~),
                libavutil-dev (>= 7:3.4.8~),
                libcap-dev [linux-any],

extras/packaging/gnu-linux/rules/debian/control

@@ -30,7 +30,7 @@ Build-Depends: debhelper (>= 9),
                libspeex-dev,
                libspeexdsp-dev,
                uuid-dev,
-               libavcodec-dev,
+               libavcodec-dev | libavcodec-extra-dev,
                libavutil-dev,
                libavformat-dev,
                libswscale-dev,