[LLD][COFF] Add REQUIRES: x86 to a couple of tests

[peter.smith]

Summary

Add "REQUIRES: x86" to fix buildbot failure on native AArch64 builder that does not have an x86 backed compiled in. Log: http://lab.llvm.org:8011/builders/clang-cmake-aarch64-lld/builds/6711/steps/ninja%20check%201

[ruiu]

LGTM

test/COFF/export-stdcall.s

+# REQUIRES: x86
 # RUN: llvm-mc -triple i686-windows-msvc %s -o %t.obj -filetype=obj
 # RUN: lld-link %t.obj -out:%t.dll -dll -nodefaultlib -noentry -export:foo_std=bar_std -export:foo_fast=bar_fast
 # RUN: llvm-nm %t.lib | FileCheck %s
 
 # MSVC fudges the lookup of 'bar' to allow it to find the stdcall function
 # _bar_std@8, and then exports _foo_std@8. Same for fastcall and other mangling
 # schemes.
 

test/COFF/export-weak-alias.s

+# REQUIRES: x86
 # RUN: llvm-mc -triple x86_64-windows-msvc %s -o %t.obj -filetype=obj
 # RUN: lld-link %t.obj -out:%t.dll -dll -nodefaultlib -noentry
 # RUN: llvm-nm %t.lib | FileCheck %s
 
 # CHECK: export-weak-alias.s.tmp.dll:
 # CHECK: 00000000 T __imp_foo_dll{{$}}
 # CHECK: 00000000 T foo_dll{{$}}