Disable libavif on x86_64 simulators.

Author: freakboy3742

.github/workflows/wheels-dependencies.sh

@@ -286,7 +286,12 @@ function build {
         build_tiff
     fi
 
-    build_libavif
+    if [[ -z "$IOS_SDK" ]] || [[ "$PLAT" == "arm64" ]]; then
+        # Building libavif for x86_64 iOS simulator isn't currently possible
+        # because it requires the use of nasm, which doesn't create
+        # iOS-compatible binaries.
+        build_libavif
+    fi
     build_libpng
     build_lcms2
     build_openjpeg

checks/check_wheel.py

@@ -27,6 +27,10 @@ def test_wheel_modules() -> None:
         # tkinter is not available on iOS
         expected_modules.remove("tkinter")
 
+        # libavif is not available on x86_64 iOS simulators
+        if platform.machine() == "x86_64":
+            expected_modules.remove("avif")
+
     assert set(features.get_supported_modules()) == expected_modules