[llvm] [Targets] Migrate from atomic_load_8/16/32/64 to atomic_load_nonext_8/16/32/64. NFC (PR #137428)

[Matt Arsenault via llvm-commits]

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@@ -502,15 +502,15 @@ def zextloadi16_#as : PatFrag<(ops node:$ptr), (zextloadi16 node:$ptr)> {
   let IsLoad = 1;
 }
 
-def atomic_load_16_#as : PatFrag<(ops node:$ptr), (atomic_load_16 node:$ptr)> {
+def atomic_load_nonext_16_#as : PatFrag<(ops node:$ptr), (atomic_load_nonext_16 node:$ptr)> {
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arsenm wrote:

That would be better, but requires touching more code at once 

https://github.com/llvm/llvm-project/pull/137428