MLK-17275-4: drm/imx: nwl_dsi-imx: Update driver for reconfig

MLK-17275-4: drm/imx: nwl_dsi-imx: Update driver for reconfig

Initially, this driver was designed to work with NWL driver as a
drm_bridge and it is required for this to work, otherwise it will defer.
When CONFIG_OF_DYNAMIC is used, the NWL bridge can be disabled by it's
remote endpoint, it that endpoint is an i2c capable device and it fails
to find a physical device on the expected i2c address.
If the NWL drm_bridge is disabled, since this driver it is required by
the master DRM device, just do nothing, so the drm_encoder won't be
created. So, if the NWL drm_bridge is missing, this driver will just do
nothing, in order to not interfere with the other available devices
required by the DRM master.

Signed-off-by: Robert Chiras <robert.chiras@nxp.com>
Reviewed-by: Laurentiu Palcu <laurentiu.palcu@nxp.com>