Input: pwm-vibra - stop regulator after disabling pwm, not before

This patch fixes order of disable calls in pwm_vibrator_stop.
Currently when starting device, we first enable vcc regulator and then
setup and enable pwm. When stopping, we should do this in oposite order,
so first disable pwm and then disable regulator.
Previously order was the same as in start.

Signed-off-by: Paweł Chmiel <pawel.mikolaj.chmiel@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>