[x86][inline-asm][ms-compat] legalize the use of "jc/jz short <op>"

[coby]

Summary

MS ignores the keyword "short" when used after a jc/jz instruction, LLVM ought to do the same.
llvm: D35892

cfe/trunk/test/CodeGen/ms-inline-asm.c

void label5() {
   }
   // CHECK-LABEL: define void @label5
   // CHECK: call void asm sideeffect inteldialect "jmp {{.*}}__MSASMLABEL_.${:uid}__dollar_label$$\0A\09{{.*}}__MSASMLABEL_.${:uid}__dollar_label$$:", "~{dirflag},~{fpsr},~{flags}"()
 }
 
 void label6(){
   __asm {
       jmp short label
+      jc  short label
+      jz  short label
     label:
   }
   // CHECK-LABEL: define void @label6
-  // CHECK: call void asm sideeffect inteldialect "jmp {{.*}}__MSASMLABEL_.${:uid}__label\0A\09{{.*}}__MSASMLABEL_.${:uid}__label:", "~{dirflag},~{fpsr},~{flags}"()
+  // CHECK: jmp {{.*}}__MSASMLABEL_.${:uid}__label\0A\09jc {{.*}}__MSASMLABEL_.${:uid}__label\0A\09jz {{.*}}__MSASMLABEL_.${:uid}__label\0A\09{{.*}}__MSASMLABEL_.${:uid}__label:"
 }
 
 // Don't include mxcsr in the clobber list.
 void mxcsr() {
   char buf[4096];
   __asm fxrstor buf
 }
 // CHECK-LABEL: define void @mxcsr