fs: move filp_close() outside of __close_fd_get_file()

Just one caller of this, and just use filp_close() there manually.
This is important to allow async close/removal of the fd.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
(cherry picked from commit 6e802a4ba056a6f2f51ac9d54eead3ed6f9829a2)