staging: unisys: visorbus: Merge vmcallinterface.h into visorchipset.c

The contents of vmcallinterface.h are better placed within
visorchipset.c from an organizational perspective. The values are only
used in that file.

Signed-off-by: David Binder <david.binder@unisys.com>
Signed-off-by: David Kershner <david.kershner@unisys.com>
Reviewed-by: Tim Sell <timothy.sell@unisys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>