video: Add new aspect ratios for HDMI 2.0

HDMI 2.0/CEA-861-F introduces two new aspect ratios:
- 64:27
- 256:135

This patch adds enumeration for the new aspect ratios
in the existing aspect ratio list.

V2: rebase
V3: rebase
V4: Added r-b from Jose, Ack by Tomi

Signed-off-by: Shashank Sharma <[e-mail]>
Reviewed-by: Sean Paul <[e-mail]>
Reviewed-by: Jose Abreu <[e-mail]>
Acked-by: Tomi Valkeinen <[e-mail]>
Cc: Daniel Vetter <[e-mail]>
Cc: Emil Velikov <[e-mail]>
Signed-off-by: Daniel Vetter <[e-mail]>
Link: http://patchwork.freedesktop.org/patch/msgid/[e-mail]

drivers/video/hdmi.c

···
 		return "4:3";
 	case HDMI_PICTURE_ASPECT_16_9:
 		return "16:9";
+	case HDMI_PICTURE_ASPECT_64_27:
+		return "64:27";
+	case HDMI_PICTURE_ASPECT_256_135:
+		return "256:135";
 	case HDMI_PICTURE_ASPECT_RESERVED:
 		return "Reserved";
 	}

include/linux/hdmi.h

···
 	HDMI_PICTURE_ASPECT_NONE,
 	HDMI_PICTURE_ASPECT_4_3,
 	HDMI_PICTURE_ASPECT_16_9,
+	HDMI_PICTURE_ASPECT_64_27,
+	HDMI_PICTURE_ASPECT_256_135,
 	HDMI_PICTURE_ASPECT_RESERVED,
 };