musescore: Fix some qt issues

- Force use QT_QPA_PLATFORM=xcb since setting it to `wayland` causes
  some GUI issues.
- Use qt515 - There are no issues with it at least now (it was set to
  qt514 in commit c3cd2be2e2).
- Don't disable QML cache since it's been a long time since the update
  from 3.4.2 to 3.5.0 of musescore.
- Add @doronbehar as maintainer.

pkgs/applications/audio/musescore/default.nix

@@ -29,9 +29,9 @@ mkDerivation rec {
   qtWrapperArgs = [
     # MuseScore JACK backend loads libjack at runtime.
     "--prefix LD_LIBRARY_PATH : ${lib.makeLibraryPath [ libjack2 ]}"
-    # Work around crash on update from 3.4.2 to 3.5.0
-    # https://bugreports.qt.io/browse/QTBUG-85967
-    "--set QML_DISABLE_DISK_CACHE 1"
+    # There are some issues with using the wayland backend, see:
+    # https://musescore.org/en/node/321936
+    "--set QT_QPA_PLATFORM xcb"
   ];
 
   nativeBuildInputs = [ cmake pkg-config ];
@@ -49,7 +49,7 @@ mkDerivation rec {
     description = "Music notation and composition software";
     homepage = "https://musescore.org/";
     license = licenses.gpl2;
-    maintainers = with maintainers; [ vandenoever turion ];
+    maintainers = with maintainers; [ vandenoever turion doronbehar ];
     platforms = platforms.linux;
     repositories.git = "https://github.com/musescore/MuseScore";
   };

pkgs/top-level/all-packages.nix

@@ -27023,7 +27023,7 @@ with pkgs;
     if stdenv.isDarwin then
       callPackage ../applications/audio/musescore/darwin.nix { }
     else
-      libsForQt514.callPackage ../applications/audio/musescore { };
+      libsForQt5.callPackage ../applications/audio/musescore { };
 
   mmh = callPackage ../applications/networking/mailreaders/mmh { };
   mutt = callPackage ../applications/networking/mailreaders/mutt { };