drm: xlnx: zynqmp_dpsub: Update dependencies for ZynqMP DP

ZynqMP DP requires the ZynqMP PHY and DPDMA to operate properly. So
depend on both the PHY and DPDMA.
Signed-off-by: Dylan Yip <dylan.yip@xilinx.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

drivers/gpu/drm/xlnx/Kconfig

@@ -3,6 +3,8 @@ config DRM_ZYNQMP_DPSUB
 	depends on ARCH_ZYNQMP || COMPILE_TEST
 	depends on COMMON_CLK && DRM && OF
 	depends on DMADEVICES
+	depends on PHY_XILINX_ZYNQMP
+	depends on XILINX_ZYNQMP_DPDMA
 	select DMA_ENGINE
 	select DRM_GEM_CMA_HELPER
 	select DRM_KMS_CMA_HELPER