qt6-pdf: don't error on xnnpack incompatible pointer types

srcpkgs/qt6-pdf/patches/qtwebengine-6.8.1-aarch64-xnnpack.patch

@@ -0,0 +1,20 @@
+Source: https://github.com/gentoo/gentoo/blob/master/dev-qt/qtwebengine/files/qtwebengine-6.8.1-aarch64-xnnpack.patch
+
+Patch status: *seems* fixed in Qt 6.9+
+
+Temporary (lame) workaround for [1] given backporting[2] (which
+is believed to be the fix) does not seem trivial. A better fix
+is welcome if have one and can test it, but otherwise this can
+likely be removed in Qt 6.9.0.
+
+[1] https://bugs.gentoo.org/945843
+[2] https://github.com/google/XNNPACK/pull/1789
+--- a/src/3rdparty/chromium/third_party/xnnpack/BUILD.gn
++++ b/src/3rdparty/chromium/third_party/xnnpack/BUILD.gn
+@@ -27,4 +27,5 @@
+ 
++  cflags = [ "-Wno-error=incompatible-pointer-types" ]
+   if (is_clang || !is_win) {
+-    cflags = [
++    cflags += [
+       "-Wno-unused-function",