mediatek: pwm: add pwm driver for MediaTek SoCs

This driver support the standard PWM API for
MediaTek MT7623, MT7622 and MT7629 SoCs

Signed-off-by: Sam Shih <sam.shih@mediatek.com>
diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile
index a837c35..2c3a069 100644
--- a/drivers/pwm/Makefile
+++ b/drivers/pwm/Makefile
@@ -12,6 +12,7 @@
 
 obj-$(CONFIG_PWM_EXYNOS)	+= exynos_pwm.o
 obj-$(CONFIG_PWM_IMX)		+= pwm-imx.o pwm-imx-util.o
+obj-$(CONFIG_PWM_MTK)		+= pwm-mtk.o
 obj-$(CONFIG_PWM_ROCKCHIP)	+= rk_pwm.o
 obj-$(CONFIG_PWM_SANDBOX)	+= sandbox_pwm.o
 obj-$(CONFIG_PWM_TEGRA)		+= tegra_pwm.o