Revert "Add support for attribute 'noescape'."

This reverts commit r313722.

It looks like compiler-rt/lib/tsan/rtl/tsan_libdispatch_mac.cc cannot be
compiled because some of the functions declared in the file do not match
the ones in the SDK headers (which are annotated with 'noescape').

llvm-svn: 313725
21 files changed