Revert "_build.sh: mac-gcc hack patch test 1"

This reverts commit 7190561.

Author: vszakats

_build.sh

@@ -1279,7 +1279,6 @@ build_single_target() {
         # directories/files out of the way:
         find "${libgccdir}/include-fixed" | sort
         patch_out='dispatch os AvailabilityInternal.h'
-        patch_out=''  # TESTING 1
         patch_out+=' stdio.h'  # for Xcode 16 error: unknown type name 'FILE'
         for f in ${patch_out}; do
           if [ -r "${libgccdir}/include-fixed/${f}" ]; then