[clang] [llvm] [ARM] Adding diagnostics for mcmodel=tiny when used in invalid targets (PR #125643)

[Aaron Ballman via llvm-commits]

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@@ -1,5 +1,5 @@
 // RUN: not %clang -### -c --target=i686 -mcmodel=medium %s 2>&1 | FileCheck --check-prefix=ERR-MEDIUM %s
-// RUN: %clang --target=x86_64 -### -c -mcmodel=tiny %s 2>&1 | FileCheck --check-prefix=TINY %s
+// RUN: not %clang --target=x86_64 -### -c -mcmodel=tiny %s 2>&1 | FileCheck --check-prefix=TINY %s
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AaronBallman wrote:

I'm surprised this test is passing. Should this not be using the check prefix `ERR-TINY` now because we expect an error?

https://github.com/llvm/llvm-project/pull/125643