[X86] Correct the inline assembly implementations of __movsb/w/d/q and...

[X86] Correct the inline assembly implementations of __movsb/w/d/q and __stosw/d/q to mark registers/memory as modified

The inline assembly for these didn't mark that edi, esi, ecx are modified by movs/stos instruction. It also didn't mark that memory is modified.

This issue was reported to llvm-dev last year http://lists.llvm.org/pipermail/cfe-dev/2017-November/055863.html but no bug was ever filed.

Differential Revision: https://reviews.llvm.org/D48448

llvm-svn: 335270