[llvm] [PHIElimination] Declare MachineLoopInfo dependency for Legacy PM (PR #169693)

[Prasoon Mishra via llvm-commits]

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@@ -0,0 +1,85 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 6
+# RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx900 -run-pass=machine-loops,livevars,phi-node-elimination -no-phi-elim-live-out-early-exit -filetype=null %s 2>&1 | FileCheck %s
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PrasoonMishra wrote:

Done. 

The test was passing in the previous version too. The pattern I used `-filetype=null %s 2>&1` is used in some lit tests, for example [regpressure_printer.mir](https://github.com/llvm/llvm-project/blob/main/llvm/test/CodeGen/AMDGPU/regpressure_printer.mir#L2), and works fine. However, I understand that using `-o -` is more explicit and much clearer. I've removed the unnecessary stderr redirection since I'm checking stdout.

https://github.com/llvm/llvm-project/pull/169693