staging: bcm2835: Break MMAL support out from camera

staging: bcm2835: Break MMAL support out from camera

The BCM2835 camera host is currently the only component that uses the
VCHIQ MMAL interface. This will soon change with the upporting of
BCM2835 ISP, which make use of the same interface.

Break VCHIQ MMAL interface support out from camera host directory to
make it possible for the ISP driver to use it as well.

The only modification to the existing mmal code is the introduction of
EXPORT_SYMBOL() for symbols required by bcm2835-camera and the addition
of the module author and licenses.

Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Link: https://lore.kernel.org/r/20200623164235.29566-2-nsaenzjulienne@suse.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>