[llvm] [AMDGPU][test]added remove duplicate options for update_mc_test_check script (PR #111769)

[Brox Chen via llvm-commits]

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@@ -118,6 +119,19 @@ def main():
         default=None,
         help="Set a default -march for when neither triple nor arch are found in a RUN line",
     )
+    parser.add_argument(
+        "--remove-duplicate",
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broxigarchen wrote:

good idea. Use unique now

https://github.com/llvm/llvm-project/pull/111769