tty/serial: clean up uart_match_port

* make parameters const (as they are only read)
* return bool (as comparison results are returned)
* add \n before final return

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210519072153.3859-1-jslaby@suse.cz


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>