staging: unisys: fix NULL comparison in destroy_controlvm_payload_info()

Just remove the NULL from the check and test the pointer directly.
Signed-off-by: Benjamin Romer <benjamin.romer@unisys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/unisys/visorchipset/visorchipset_main.c

@@ -1299,7 +1299,7 @@ initialize_controlvm_payload_info(HOSTADDRESS phys_addr, u64 offset, u32 bytes,
 static void
 destroy_controlvm_payload_info(struct controlvm_payload_info *info)
 {
-	if (info->ptr != NULL) {
+	if (info->ptr) {
 		iounmap(info->ptr);
 		info->ptr = NULL;
 	}