firefox: place alsaLib in lib search patch

libcubeb has dlopened libraries for awhile now. In nixpkgs there was
support for the PulseAudio backend doing this, however the ALSA backend
support was missed and caused issue #79310 (no sound with ALSA). This
gives ALSA users the ability to hear sound once again.

pkgs/applications/networking/browsers/firefox/common.nix

@@ -333,6 +333,7 @@ buildStdenv.mkDerivation ({
     version = ffversion;
     isFirefox3Like = true;
     gtk = gtk2;
+    inherit alsaSupport;
     inherit nspr;
     inherit ffmpegSupport;
     inherit gssSupport;