MFC r259100:

Pull in r196658 from upstream clang trunk:

  CodeGen: Don't emit linkage on thunks that aren't emitted because they're
  vararg.

  This can happen when we're trying to emit a thunk with available_externally
  linkage with optimization enabled but bail because it doesn't make sense for
  vararg functions.

  [LLVM] PR18098.

This should fix clang "Broken module found, compilation aborted" errors when
building the qt4-based dvbcut port.

Reported by:	se
MFC r259111:

Use correct casts in gcc's emmintrin.h for the first arguments of the
following builtin functions:

* __builtin_ia32_pslldi128() takes __v4si instead of __v8hi
* __builtin_ia32_psllqi128() takes __v2di instead of __v8hi
* __builtin_ia32_psradi128() takes __v4si instead of __v8hi

This should fix the following errors when building the LINT kernel with
gcc:

sys/crypto/aesni/aesni_wrap.c:191: error: incompatible type for argument 1 of
'__builtin_ia32_psradi128'
sys/crypto/aesni/aesni_wrap.c:195: error: incompatible type for argument 1 of
'__builtin_ia32_pslldi128'