extcon: Add EXTCON_DISP_CVBS and EXTCON_DISP_EDP

Add EXTCON_DISP_CVBS for Composite Video Broadcast Signal.
Add EXTCON_DISP_EDP for Embedded Display Port

[1] https://en.wikipedia.org/wiki/Composite_video
[2] https://en.wikipedia.org/wiki/DisplayPort#eDP



Signed-off-by: Michael Wu <michael@allwinnertech.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>