draonboard: Remove obsolete debug.sf.no_hw_vsync usage

Working with Caleb, I noticed we have had this property
set the entire time. It doesn't do anything these days
so its safe to remove.

Signed-off-by: John Stultz <john.stultz@linaro.org>
Change-Id: Ie7e37630265297337ec376a45d28b8460ddf665c
1 file changed