[CrashReproducer] Add -fmodule-cache-path to reproducer script

The cc1 invocation in the reproducer script should contain a valid path in
-fmodule-cache-path; for that reuse "<name>.cache/module" dir we already
use to dump the vfs and modules.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@265162 91177308-0d34-0410-b5e6-96231b3b80d8