[llvm] [AMDGPU] Reorganize tests to unblock #112403 (PR #115503)

[Shilei Tian via llvm-commits]

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@@ -0,0 +1,27 @@
+; RUN: not --crash llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx900 %s -o - 2>&1 | FileCheck -enable-var-scope %s
+
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shiltian wrote:

> Also replace -o - with -filetype=null

Is that what we prefer to use now?

https://github.com/llvm/llvm-project/pull/115503