Input: max77693-haptic - fix state check in imax77693_haptic_disable()

The check to see whether the device is already disabled in
max77693_haptic_disable() was inversed, this change corrects it.

Signed-off-by: Jaewon Kim <jaewon02.kim@samsung.com>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>