OMAP: DSS2: DSI: Pass pointer to struct to packet_sent_handler isrs

dsi_packet_sent_handler_vp() and dsi_packet_sent_handler_l4() currently
receive the completion parameter as their argument. This is not sufficient
information to differentiate between DSI1 and DSI2 platform devices.

Pass the struct "dsi_packet_sent_handler_data" to the packet_sent_handler
isrs, these contain the platform_device pointer of the DSI device and the
pointer to the completion struct.

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