staging: unisys: visorbus: fix s-Par to boot with option CONFIG_VMAP_STACK set to y

The root issue is that we are not allowed to have items on the
stack being passed to "DMA" like operations. In this case we have
vmcall operation that was using parameters from the stack.

This patch fixes the issue by moving the variables on stack in
issue_vmcall_io_controlvm_addr() to vmcall_controlvm_addr struct.

Signed-off-by: Sameer Wadgaonkar <sameer.wadgaonkar@unisys.com>
Signed-off-by: David Kershner <david.kershner@unisys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>