[llvm] [LV] Fix ScalarIVSteps vplan pattern matcher, remove m_CanonicalIV() (PR #138298)

[Florian Hahn via llvm-commits]

================
@@ -0,0 +1,46 @@
+//===- llvm/unittests/Transforms/Vectorize/VPlanPatternMatchTest.cpp ------===//
----------------
fhahn wrote:

>From the description, I assume it is not possible to expose this currently with an IR unit test?

https://github.com/llvm/llvm-project/pull/138298