Staging: vme: add VME Location Monitor management mechanism

Extend the image and DMA channel resource management methods to control the
location monitor resource. The location monitor should be controlled as it can
only be used at a single location at a time.

Signed-off-by: Martyn Welch <martyn.welch@gefanuc.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>