The line buffer sizes vary across DSI modules, create a function
dsi_get_line_buf_size() using DSI_GNQ register to get the size of
line buffer used for the DISPC video port data.
Signed-off-by: NArchit Taneja <archit@ti.com>
Signed-off-by: NTomi Valkeinen <tomi.valkeinen@ti.com>