Remove dead .seh_stackalloc parsing method in X86AsmParser
Remove dead .seh_stackalloc parsing method in X86AsmParser

The shared COFF asm parser code handles this directive, since it is
shared with AArch64. Spotted by Alexandre Ganea in review.

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@371251 91177308-0d34-0410-b5e6-96231b3b80d8

GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm