drm/dsi: Use mipi_dsi_device_register_full for DSI device creation

Use mipi_dsi_device_register_full for device creation. This takes in
mipi_dsi_device_info as a template to populate the DSI device information.

The reason to introduce this is to have a way to create DSI devices not
available via DT. Drivers that want to create a DSI device can populate
mipi_dsi_device_info and call this function. For DSI devices available
via DT, of_mipi_dsi_device_add is used as before, but this now calls
mipi_dsi_device_register_full internally.

Signed-off-by: Archit Taneja <architt@codeaurora.org>