linux-phytec-fsl

OMAPDSS: DPI: fix LCD3 DSI source

At the moment the dpi driver does not handle LCD3 clock source at all.

LCD3 channel gets the DSI PLL clock from DSI2 instance. Add support for
LCD3's clock source in the dpi driver.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>