OMAP: DSS2: DSI: enable interface for omap4

By default, the DSI is not getting enabled for omap4.
OMAP2PLUS does not catch this issue since it has ARCH_OMAP3.

The issue is only seen when using defconfig with ARCH_OMAP4 only.
Signed-off-by: Vikram Pandita <vikram.pandita@ti.com>
Cc: Archit Taneja <archit@ti.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drivers/video/omap2/dss/Kconfig

@@ -80,7 +80,7 @@ config OMAP2_DSS_SDI
 
 config OMAP2_DSS_DSI
 	bool "DSI support"
-	depends on ARCH_OMAP3
+	depends on ARCH_OMAP3 || ARCH_OMAP4
         default n
 	help
 	  MIPI DSI (Display Serial Interface) support.