[ASAN] Revert r313303 - Add macro denoting availability of new...

[ASAN] Revert r313303 - Add macro denoting availability of new `__asan_handle_no_return()` function.

It was pointed out that compiler-rt has always defined the symbol, but only
recently added it to the public headers. Meaning that libc++abi can re-declare
it instead of needing this macro.

llvm-svn: 313306