drm: add picture aspect ratio flags

This patch adds drm flag bits for aspect ratio information

Currently drm flag bits don't have field for mode's picture
aspect ratio. This field will help the driver to pick mode with
right aspect ratio, and help in setting right VIC field in avi
infoframes.

V2: Addressed review comments from Sean
- Changed PAR-> PIC_AR
V3: Rebase
V3: Added r-b by Jose
Signed-off-by: Shashank Sharma <shashank.sharma@intel.com>
Reviewed-by: Jim Bride <jim.bride@linux.intel.com>
Reviewed-by: Jose Abreu <Jose.Abreu@synopsys.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Emil Velikov <emil.l.velikov@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1476705880-15600-2-git-send-email-shashank.sharma@intel.com

include/uapi/drm/drm_mode.h

@@ -77,6 +77,19 @@ extern "C" {
 #define  DRM_MODE_FLAG_3D_TOP_AND_BOTTOM	(7<<14)
 #define  DRM_MODE_FLAG_3D_SIDE_BY_SIDE_HALF	(8<<14)
 
+/* Picture aspect ratio options */
+#define DRM_MODE_PICTURE_ASPECT_NONE		0
+#define DRM_MODE_PICTURE_ASPECT_4_3		1
+#define DRM_MODE_PICTURE_ASPECT_16_9		2
+
+/* Aspect ratio flag bitmask (4 bits 22:19) */
+#define DRM_MODE_FLAG_PIC_AR_MASK		(0x0F<<19)
+#define  DRM_MODE_FLAG_PIC_AR_NONE \
+			(DRM_MODE_PICTURE_ASPECT_NONE<<19)
+#define  DRM_MODE_FLAG_PIC_AR_4_3 \
+			(DRM_MODE_PICTURE_ASPECT_4_3<<19)
+#define  DRM_MODE_FLAG_PIC_AR_16_9 \
+			(DRM_MODE_PICTURE_ASPECT_16_9<<19)
 
 /* DPMS flags */
 /* bit compatible with the xorg definitions. */
@@ -92,11 +105,6 @@ extern "C" {
 #define DRM_MODE_SCALE_CENTER		2 /* Centered, no scaling */
 #define DRM_MODE_SCALE_ASPECT		3 /* Full screen, preserve aspect */
 
-/* Picture aspect ratio options */
-#define DRM_MODE_PICTURE_ASPECT_NONE	0
-#define DRM_MODE_PICTURE_ASPECT_4_3	1
-#define DRM_MODE_PICTURE_ASPECT_16_9	2
-
 /* Dithering mode options */
 #define DRM_MODE_DITHERING_OFF	0
 #define DRM_MODE_DITHERING_ON	1