[llvm] [NFC][SPIRV] Move `SPIRVStripConvergenceIntrinsics` to Utils (PR #188537)

[Nathan Gauër via llvm-commits]

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@@ -0,0 +1,58 @@
+; RUN: opt -passes=strip-convergence-intrinsics -S < %s | FileCheck %s
+
+; Verify that convergence intrinsics and convergencectrl operand bundles are
+; stripped by the pass.
+
+define void @entry_and_call() convergent {
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Keenuts wrote:

You should add the test Deric mentioned: a block following a block it dominates in the CFG with intrinsincs to cleanup. 

https://github.com/llvm/llvm-project/pull/188537