bug: use POSIX compliant techniques for cpio and rm

These changes are compatible with basic macOS implementations of cpio and rm

Signed-off-by: Paul Charlton <techguru@byiq.com>

build.sh

@@ -99,7 +99,7 @@ fi
 echo "Copying files..."
 
 cp -r "$SRC"/* "$PACKAGE/"
-rm "$PACKAGE/asahi_firmware"
+rm -rf "$PACKAGE/asahi_firmware"
 cp -r "$AFW" "$PACKAGE/"
 if [ -r "$LOGO" ]; then
     cp "$LOGO" "$PACKAGE/logo.icns"
@@ -122,7 +122,7 @@ echo "Extracting Python framework..."
 mkdir -p "$PACKAGE/Frameworks/Python.framework"
 
 7z x -so "$DL/$PYTHON_PKG" Python_Framework.pkg/Payload | zcat | \
-    cpio -i -D "$PACKAGE/Frameworks/Python.framework"
+    (cd "$PACKAGE/Frameworks/Python.framework"; cpio -i)
 
 
 cd "$PACKAGE/Frameworks/Python.framework/Versions/Current"