drm/tilcdc: Fix tilcdc component master unloading

Fix tilcdc component master unloading. If a subcomponent module
(tda998x in this case) is unloaded before its master (tilcdc in this
case), it calls drm_put_dev() and it should not be called again by
the master when its module is unloaded. However component_master_del()
must still be called and the check if the drm_put_dev() has been
called must be in component_master_ops unbind() callback, not in
platform_driver remove() callback.

Signed-off-by: Jyri Sarha <jsarha@ti.com>