fix(apparmor): Fix loading libraries from custom install prefix

If qtox is installed in /usr/local prefix (for example), launching qTox
fails because loading libraries from @{qtox_prefix} directory was not
allowed.

Add rule to allow loading libraries from @{qtox_prefix}/lib directory.

security/apparmor/2.12.1/usr.bin.qtox

@@ -27,6 +27,11 @@ profile qtox /usr{,/local}/bin/qtox {
   #TODO: use xdg-open abstraction when it's available
   /usr/bin/xdg-open PUx,
 
+  # Additional libraries
+
+  # Allow /usr/local/lib/libtoxcore.so...
+  @{qtox_prefix}/lib/*.so* mr,
+
   # Networking
 
   network tcp,

security/apparmor/2.13.2/usr.bin.qtox

@@ -33,6 +33,11 @@ profile qtox /usr{,/local}/bin/qtox {
   #TODO: use xdg-open abstraction when it's available
   /usr/bin/xdg-open PUx,
 
+  # Additional libraries
+
+  # Allow /usr/local/lib/libtoxcore.so...
+  @{qtox_prefix}/lib/*.so* mr,
+
   # Networking
 
   network tcp,