vhost: whitespace fix

Fix up whitespace in vq_memory_access_ok.
Reported-by: Aristeu Rozanski <aris@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

drivers/vhost/vhost.c

@@ -237,8 +237,8 @@ static int vq_memory_access_ok(void __user *log_base, struct vhost_memory *mem,
 {
 	int i;
 
-        if (!mem)
-                return 0;
+	if (!mem)
+		return 0;
 
 	for (i = 0; i < mem->nregions; ++i) {
 		struct vhost_memory_region *m = mem->regions + i;