[llvm] [llvm] Remove `undef` from `llvm/test/Transforms` tests (PR #123889)

[via llvm-commits]

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@@ -33,7 +33,7 @@
 
 define i16 @test1() {
 entry:
-  call void @llvm.dbg.declare(metadata ptr undef, metadata !4, metadata !DIExpression()), !dbg !16
+  call void @llvm.dbg.declare(metadata ptr null, metadata !4, metadata !DIExpression()), !dbg !16
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Yeaseen wrote:

Yeah. I got the subtlety here. 

https://github.com/llvm/llvm-project/pull/123889