hwc: enable vsync for external display

- wait for hdmi vsync when connected to hdmi
- add commit to call PANDISPLAY for updating ext display
- add functions to close fb and reset info

Change-Id: I49afbeb85935b111055a872b29a1f65d87ab72c9
Acked-by: Arun Kumar K.R <akumarkr@codeaurora.org>
5 files changed