pwm: mediatek: Don't explicitly set .owner

drivers/pwm/pwm-mediatek.c:210:3-8: No need to set .owner here. The core will do it.

 Remove .owner field if calls are used which set it automatically

Generated by: scripts/coccinelle/api/platform_no_drv_owner.cocci

CC: John Crispin <john@phrozen.org>
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>