[llvm] [AMDGPU][GlobalISel] Update G_TRUNC tests (PR #180647)

[Petar Avramovic via llvm-commits]

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@@ -1,5 +1,5 @@
 # NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 5
-# RUN: llc -mtriple=amdgcn -mcpu=gfx1010 -run-pass=regbankselect %s -verify-machineinstrs -o - | FileCheck %s -check-prefixes=OLD_RBS
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petar-avramovic wrote:

test very intentionally tests only the regbankselect pass

https://github.com/llvm/llvm-project/pull/180647