[CodeGen] Use MIR syntax for MachineMemOperand printing

Get rid of the "; mem:" suffix and use the one we use in MIR: ":: (load 2)".

rdar://38163529

Differential Revision: https://reviews.llvm.org/D42377

llvm-svn: 327580
diff --git a/llvm/test/CodeGen/AMDGPU/extload-align.ll b/llvm/test/CodeGen/AMDGPU/extload-align.ll
index 4df4b26..ed6890e 100644
--- a/llvm/test/CodeGen/AMDGPU/extload-align.ll
+++ b/llvm/test/CodeGen/AMDGPU/extload-align.ll
@@ -7,7 +7,7 @@
 ; size and not 4 corresponding to the sign-extended size (i32).
 
 ; DEBUG: {{^}}# Machine code for function extload_align:
-; DEBUG: mem:LD2[<unknown>(addrspace=5)]
+; DEBUG: (load 2, addrspace 5)
 ; DEBUG: {{^}}# End machine code for function extload_align.
 
 define amdgpu_kernel void @extload_align(i32 addrspace(5)* %out, i32 %index) #0 {