qmake: fix Android version code for RCs

This removes rc version strings from the Android version code which
does not allow for anything but numbers. This is just to fix the release
candidate builds.

QGCCommon.pri

@@ -233,6 +233,10 @@ AndroidBuild {
         DEV_VERSION = $$join(DEV_VERSION, "", "0")
     }
 
+    # Use a shell command to strip "rc" and everything after it.
+    # Otherwise rc version tags will break the Android build.
+    PATCH_VERSION = $$system(echo $$PATCH_VERSION | sed 's/rc.*//')
+
     # Bitness for android version number is 66/34 instead of 64/32 in because of a required version number bump screw-up ages ago
     equals(ANDROID_TARGET_ARCH, arm64-v8a)  {
         ANDROID_TRUE_BITNESS = 64