ARM: imx_v6_v7_defconfig: Enable PWM and backlight options

These options are useful for controlling backlight contrast via PWM.
Signed-off-by: NFabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>

arch/arm/configs/imx_v6_v7_defconfig

@@ -171,6 +171,7 @@ CONFIG_BACKLIGHT_LCD_SUPPORT=y
 CONFIG_LCD_CLASS_DEVICE=y
 CONFIG_LCD_L4F00242T03=y
 CONFIG_BACKLIGHT_CLASS_DEVICE=y
+CONFIG_BACKLIGHT_PWM=y
 CONFIG_FRAMEBUFFER_CONSOLE=y
 CONFIG_FRAMEBUFFER_CONSOLE_DETECT_PRIMARY=y
 CONFIG_FONTS=y
@@ -216,6 +217,8 @@ CONFIG_DRM_IMX_IPUV3_CORE=y
 CONFIG_DRM_IMX_IPUV3=y
 CONFIG_COMMON_CLK_DEBUG=y
 # CONFIG_IOMMU_SUPPORT is not set
+CONFIG_PWM=y
+CONFIG_PWM_IMX=y
 CONFIG_EXT2_FS=y
 CONFIG_EXT2_FS_XATTR=y
 CONFIG_EXT2_FS_POSIX_ACL=y