CFI: Move STL allocator blacklist to clang

[vlad.tsyrklevich]

Summary

The regular expression to match STL allocators can't easily account for
C++ mangling compression and fails to match some valid instances of STL
allocators. Perform this logic in clang instead.

Motivated by crbug.com/751385.

[pcc]

LGTM once your other change lands.

compiler-rt/trunk/lib/cfi/cfi_blacklist.txt

-# STL allocators (T *allocator<T *>::allocate(size_type, const void*)).
-# The type signature mandates a cast from uninitialized void* to T*.
-# size_type can either be unsigned int (j) or unsigned long (m).
-fun:*8allocateEjPKv
-fun:*8allocateEmPKv
-
 # std::get_temporary_buffer, likewise (libstdc++, libc++).
 fun:_ZSt20get_temporary_buffer*
 fun:_ZNSt3__120get_temporary_buffer*
 
 # STL address-of magic (libstdc++, libc++).
 fun:*__addressof*
 fun:_ZNSt3__19addressof*
 
 # Windows C++ stdlib headers that contain bad unrelated casts.
 src:*xmemory0
 src:*xstddef
 
 # std::_Sp_counted_ptr_inplace::_Sp_counted_ptr_inplace() (libstdc++).
 # This ctor is used by std::make_shared and needs to cast to uninitialized T*
 # in order to call std::allocator_traits<T>::construct.
 fun:_ZNSt23_Sp_counted_ptr_inplace*