[clang] AMDGPU: Remove "gws" from the “read-only” target feature list (PR #148141)

[Matt Arsenault via cfe-commits]

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@@ -1,6 +0,0 @@
-// RUN: %clang_cc1 -triple amdgcn -target-feature +gws -o /dev/null %s 2>&1 \
-// RUN:   | FileCheck --check-prefix=GWS %s
-
-// GWS: warning: feature flag '+gws' is ignored since the feature is read only [-Winvalid-command-line-argument]
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arsenm wrote:

The test should be replaced with a different example readonly feature 

https://github.com/llvm/llvm-project/pull/148141