Disable autolink_private_module.m for z/OS & AIX

This change disables it on z/OS and AIX since it fails on both platforms with:
fatal error: error in backend: Objective-C support is unimplemented for object file format

Author: zibi2

clang/test/Modules/autolink_private_module.m

@@ -1,4 +1,6 @@
 // Test that autolink hints for frameworks don't use the private module name.
+// UNSUPPORTED: target={{.*}}-zos{{.*}}, target={{.*}}-aix{{.*}}
+
 // RUN: rm -rf %t && mkdir %t
 // RUN: split-file %s %t