DRM: Armada: add support for drm tda19988 driver

Add support for TDA998x output via the slave driver in the kernel.

Reviewed-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

drivers/gpu/drm/armada/Kconfig

@@ -13,3 +13,12 @@ config DRM_ARMADA
 	  This driver provides no built-in acceleration; acceleration is
 	  performed by other IP found on the SoC.  This driver provides
 	  kernel mode setting and buffer management to userspace.
+
+config DRM_ARMADA_TDA1998X
+	bool "Support TDA1998X HDMI output"
+	depends on DRM_ARMADA != n
+	depends on I2C && DRM_I2C_NXP_TDA998X = y
+	default y
+	help
+	  Support the TDA1998x HDMI output device found on the Solid-Run
+	  CuBox.