Staging: VME: Introduce IOCTL to generate VME interrupts.

The vme_irq_set is oblviously not needed (a remnant from old tests) and the
IOCTL exchange types have been updated following Greg's comments.

Allow the IOCTL call to generate VME interrupts when called on the vme/ctl
device with the right arguments.

Signed-off-by: Vincent Bossier <vincent.bossier@gmail.com>
Acked-by: Martyn Welch <martyn.welch@ge.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>