[llvm] [NVPTX] Add intrinsics for wgmma.fence PTX instructions (PR #120523)

[Durgadoss R via llvm-commits]

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@@ -0,0 +1,37 @@
+; RUN: llc < %s -march=nvptx64 -mcpu=sm_90a -mattr=+ptx80 | FileCheck %s
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durga4github wrote:

optional: We mostly generate these checks through utils/update_llc_test_checks.py.
But since these are one-liner checks, I think this is fine.

https://github.com/llvm/llvm-project/pull/120523