Regression starting GHC 8.8: `-optP` preprocessor options passed to C compiler

Lifted from https://github.com/haskell/cabal/issues/8058: In the wild (macOS, with cpp-11 installed):

cabal install -w ghc-8.6.5 fudgets-0.18.3.1

(Works.)

cabal-3.7 install -w ghc-8.8.4 fudgets-0.18.3.1

(Fails, with cabal-install-3.7 from master.)

Starting with GHC 8.8, option -optP -traditional is passed to the C compiler, not just the preprocessor:

On macOS (test by @phadej):

touch foo.c
ghc  -optP -traditional -v3 -c -o foo.o foo.c

This works up to GHC 8.6, e.g.

*** C Compiler:
gcc ... -x c foo.c ...

But it breaks from GHC 8.8 upward, e.g.:

** C Compiler:
gcc -x c foo.c ... -Xpreprocessor -traditional
error: unknown argument: '-traditional'

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