Reduce cost of setting video mode information when using
vsync_adjust=1/2 or vscale_mode=4/5 from 90ms to 5ms (worst case, most
instances are less than 1ms).
Split video initialization into video_init and video_set_mode.
video_init is called once, video_set_mode is called whenever the mode
changes.
Split hdmi_config into hdmi_config_init and hdmi_config_set_mode. Same
as video_, hdmi_config_init does the bulk of the initialization,
hdmi_config_set_mode is just for parameters that can change based on the
mode.
Load video filter data in loadScalerCfg and persist it.
Calculate a digest for scaler data and use that to determine whether new
data needs to be sent.
Only send gamma information if the filename has changed.
Offload fb module parameter writing to a separate thread via the new
offload system.
Reduce the amount of work being done in set_vrr_mode when vrr is
disabled.
