fuse: respect FOPEN_KEEP_CACHE on opendir

fuse: respect FOPEN_KEEP_CACHE on opendir

The re-factoring of fuse_dir_open() missed the need to invalidate
directory inode page cache with open flag FOPEN_KEEP_CACHE.

Fixes: 7de64d521bf92 ("fuse: break up fuse_open_common()")
Reported-by: Prince Kumar <princer@google.com>
Closes: https://lore.kernel.org/linux-fsdevel/CAEW=TRr7CYb4LtsvQPLj-zx5Y+EYBmGfM24SuzwyDoGVNoKm7w@mail.gmail.com/
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Link: https://lore.kernel.org/r/20250101130037.96680-1-amir73il@gmail.com
Reviewed-by: Bernd Schubert <bernd.schubert@fastmail.fm>
Signed-off-by: Christian Brauner <brauner@kernel.org>