OMAPDSS: APPLY: Add manager timings as extra_info in private data

DISPC manager size and DISPC manager blanking parameters(for LCD managers)
follow the shadow register programming model. Currently, they are programmed
directly by the interface drivers.

To configure manager timings using APPLY, there is a need to introduce extra
info flags for managers, similar to what is done for overlays. This is needed
because timings aren't a part of overlay_manager_info struct configured by a
user of DSS, they are configured internally by the interface or panel drivers.

Add dirty and shadow_dirty extra_info flags for managers, update these flags
at the appropriate places. Rewrite the function extra_info_update_ongoing()
slightly as checking for manager's extra_info flags can simplify the code a bit.

Create function dss_mgr_set_timings() which applies the new manager timings to
extra_info.

Signed-off-by: Archit Taneja <archit@ti.com>