commit acf47d4f upstream.

Fix potential I/O while runtime suspended due to missing PM operations
in send_setup.

Fixes: 383cedc3 ("USB: serial: full autosuspend support for the
option driver")
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>