[llvm] [AMDGPU] RewriteMFMAFormStage: fix SpillCost early-return missing reset (PR #199708)

[Shilei Tian via llvm-commits]

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@@ -0,0 +1,642 @@
+; NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 6
+; RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx950 -amdgpu-disable-rewrite-mfma-form-sched-stage=false -verify-machineinstrs -stop-after=machine-scheduler < %s | FileCheck %s
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shiltian wrote:

```suggestion
; RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx950 -amdgpu-disable-rewrite-mfma-form-sched-stage=false -stop-after=machine-scheduler < %s | FileCheck %s
```

https://github.com/llvm/llvm-project/pull/199708