[clang] Fix erroneous warning. (PR #79821)

[Aaron Ballman via cfe-commits]

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@@ -44,3 +47,4 @@
 // CHECK-NOT: -complex-range=fortran
 // WARN1: warning: overriding '-fcx-limited-range' option with '-fcx-fortran-rules' [-Woverriding-option]
 // WARN2: warning: overriding '-fcx-fortran-rules' option with '-fcx-limited-range' [-Woverriding-option]
+// range-no-diagnostics
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AaronBallman wrote:

CC @MaskRay is this a reasonable way to test or should we be using `CHECK-NOT` and not using `-verify` because the diagnostics come from the driver?

https://github.com/llvm/llvm-project/pull/79821