[llvm] [AMDGPU][LIT][NFC] Added xfail test for live-in CSR SGPR used partially (PR #126696)

[Diana Picus via llvm-commits]

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@@ -0,0 +1,52 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py
+# RUN: llc -mtriple=amdgcn-amd-amdhsa -verify-machineinstrs -run-pass=si-lower-sgpr-spills -o - %s | FileCheck %s
+# XFAIL: *
+
+# FIXME : Currently, MRI's liveIn check for regiters does not take corresponding live-in's sub-registers in account. As a result
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rovka wrote:

```suggestion
# FIXME : Currently, MRI's liveIn check for registers does not take the corresponding live-in's sub-registers into account. As a result
```

https://github.com/llvm/llvm-project/pull/126696