drm/komeda: add NV12 format to support writeback layer type

When testing the d71 writeback layer function,
the output format is set to NV12, and the following error message is displayed:

[drm:komeda_fb_is_layer_supported] Layer TYPE: 4 doesn't support fb FMT: NV12 little-endian (0x3231564e) with modifier: 0x0..

Check the d71 data manual, writeback layer output formats includes NV12 format.
Signed-off-by: baozhu.liu <lucas.liu@siengine.com>
Signed-off-by: Liviu Dudau <liviu.dudau@arm.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230829093004.22860-1-lucas.liu@siengine.com

drivers/gpu/drm/arm/display/komeda/d71/d71_dev.c

@@ -521,7 +521,7 @@ static struct komeda_format_caps d71_format_caps_table[] = {
 	{__HW_ID(5, 1),	DRM_FORMAT_YUYV,	RICH,		Rot_ALL_H_V,	LYT_NM, AFB_TH}, /* afbc */
 	{__HW_ID(5, 2),	DRM_FORMAT_YUYV,	RICH,		Flip_H_V,		0, 0},
 	{__HW_ID(5, 3),	DRM_FORMAT_UYVY,	RICH,		Flip_H_V,		0, 0},
-	{__HW_ID(5, 6),	DRM_FORMAT_NV12,	RICH,		Flip_H_V,		0, 0},
+	{__HW_ID(5, 6),	DRM_FORMAT_NV12,	RICH_WB,	Flip_H_V,		0, 0},
 	{__HW_ID(5, 6),	DRM_FORMAT_YUV420_8BIT,	RICH,		Rot_ALL_H_V,	LYT_NM, AFB_TH}, /* afbc */
 	{__HW_ID(5, 7),	DRM_FORMAT_YUV420,	RICH,		Flip_H_V,		0, 0},
 	/* YUV 10bit*/