OMAP: DSS2: Add SPI dependency to Kconfig of ACX565AKM panel

This panel driver is using SPI for its communication so add CONFIG_SPI
dependency.
Signed-off-by: Jarkko Nikula <jhnikula@gmail.com>
Cc: Roger Quadros <roger.quadros@nokia.com>
Cc: Tomi Valkeinen <tomi.valkeinen@nokia.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@nokia.com>

drivers/video/omap2/displays/Kconfig

@@ -40,7 +40,7 @@ config PANEL_TPO_TD043MTEA1
 
 config PANEL_ACX565AKM
 	tristate "ACX565AKM Panel"
-	depends on OMAP2_DSS_SDI
+	depends on OMAP2_DSS_SDI && SPI
 	select BACKLIGHT_CLASS_DEVICE
 	help
 	  This is the LCD panel used on Nokia N900