Staging: unisys: Fixup sparse warnings for dereferencing noderef types.

Fixed the usage of the following so they don't try to dereference
pointers to iomem.
	CHANNEL_U64_MISMATCH
	CHANNEL_U32_MISMATCH
	wait_for_valid_guid

Signed-off-by: Ken Cox <jkc@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>