video: mxsfb: add DM_VIDEO support

Extend the driver to build with DM_VIDEO enabled. DTS files
must additionally include 'u-boot,dm-pre-reloc' property in
soc and child nodes to enable driver binding to mxsfb device.

Signed-off-by: Igor Opaniuk <igor.opaniuk@toradex.com>
diff --git a/arch/arm/mach-imx/mx7/soc.c b/arch/arm/mach-imx/mx7/soc.c
index 7cfdff0..4a914fc 100644
--- a/arch/arm/mach-imx/mx7/soc.c
+++ b/arch/arm/mach-imx/mx7/soc.c
@@ -369,7 +369,7 @@
 void reset_misc(void)
 {
 #ifndef CONFIG_SPL_BUILD
-#ifdef CONFIG_VIDEO_MXS
+#if defined(CONFIG_VIDEO_MXS) && !defined(CONFIG_DM_VIDEO)
 	lcdif_power_down();
 #endif
 #endif