OMAPDSS: MANAGER: Check LCD related overlay manager parameters

The LCD related manager configurations are a part of the manager's private data
in APPLY. Pass this to dss_lcd_mgr_config to dss_mgr_check and create a function
to check the validity of some of the configurations.

To check some of the configurations, we require information of interface to
which the manager output is connected. These can be added once interfaces are
represented as an entity.

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