[clang] [Driver] Introduce ffp-model=aggressive (PR #100453)

[Fangrui Song via cfe-commits]

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@@ -2,13 +2,13 @@
 // and other floating point options get a warning diagnostic.
 //
 
-// RUN: %clang -### -ffp-model=fast -ffp-contract=off -c %s 2>&1 \
+// RUN: %clang -### -ffp-model=aggressive -ffp-contract=off -c %s 2>&1 \
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MaskRay wrote:

It's still useful to test the behavior of `-ffp-model=fast -ffp-contract=off`

https://github.com/llvm/llvm-project/pull/100453