[llvm] [LV][IRBuilder] Allow implicit truncation of step vector (PR #173229)

[Ramkumar Ramachandra via llvm-commits]

================
@@ -0,0 +1,56 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 6
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artagnon wrote:

```suggestion
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --check-globals none --filter-out-after "^scalar.ph" --version 6
```

https://github.com/llvm/llvm-project/pull/173229