OMAP: DSS2: LCD2 Channel Changes for DISPC

DISPC functions are modified in order to work when the manager is LCD2.
This includes:
Adding new IRQs specific to LCD2 and their handling.
Provide dumps of the new manager's registers.
Provide dumps of the new manager's clocks.
Checks for channel for registers DISPC_CONTROL2 and DISPC_CONFIG2
which can't be parametrized.

Signed-off-by: Sumit Semwal <sumit.semwal@ti.com>
Signed-off-by: Mukund Mittal <mmittal@ti.com>
Signed-off-by: Samreen <samreen@ti.com>
Signed-off-by: Archit Taneja <archit@ti.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@nokia.com>