serdev: simplify Makefile

drivers/tty/Makefile has:
	obj-$(CONFIG_SERIAL_DEV_BUS)    += serdev/

so in drivers/tty/serdev/Makefile CONFIG_SERIAL_DEV_BUS is always =y.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20191212101649.18126-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1 file changed