[clang] Move `-fprofile-instrument-use-path=` check to driver (#159667) The frontend currently opens the path provided via `-fprofile-instrument-use-path=` to learn the kind of the instrumentation data and set the `CodeGenOptions::ProfileUse` value. This happens during command-line parsing, where we don't have a correctly configured VFS yet, so the behavior is quite different from all other frontend inputs. We need to move this logic out of the frontend command line parsing logic somewhere where we do have the configured VFS. The complication is that the `ProfileUse` flag is being used to set preprocessor macros, and there isn't a great place between command line parsing and preprocessor initialization to perform this logic. This PR solves the issue by deducing the kind of instrumentation data right in the driver and then passing it via a new flag to the frontend. This shouldn't change observable behavior of Clang on the driver level, and only affects the frontend command line interface, which is an implementation detail anyway.
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