PWM: update enable status when using the internal API
Without these, 'devinfo pwmX' will show enabled=0 even though the PWM
was enabled (for example by a pwm-backlight).
Signed-off-by: Jan Luebbe <jlu@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>