[llvm] [AMDGPU] Reject illegal image atomic data widths in SelectionDAG (PR #210366)

[Matt Arsenault via llvm-commits]

================
@@ -0,0 +1,45 @@
+; RUN: not llc -mtriple=amdgcn -mcpu=gfx90a -filetype=null %s 2>&1 | FileCheck %s
----------------
arsenm wrote:

Shouldn't use xfail suffix, err suffix? xfail implies the test isn't working as expected 

https://github.com/llvm/llvm-project/pull/210366