UBI: rename sv to av

After re-naming the 'struct ubi_scan_volume' we should adjust all variables
named 'sv' to something else, because 'sv' stands for "scanning volume".
Let's rename it to 'av' which stands for "attaching volume" which is
a bit more consistent and has the same length, which makes re-naming easy.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>
diff --git a/drivers/mtd/ubi/wl.c b/drivers/mtd/ubi/wl.c
index 992240d..72fbae1 100644
--- a/drivers/mtd/ubi/wl.c
+++ b/drivers/mtd/ubi/wl.c
@@ -1384,7 +1384,7 @@
 {
 	int err, i;
 	struct rb_node *rb1, *rb2;
-	struct ubi_ainf_volume *sv;
+	struct ubi_ainf_volume *av;
 	struct ubi_ainf_peb *aeb, *tmp;
 	struct ubi_wl_entry *e;
 
@@ -1436,8 +1436,8 @@
 		ubi->lookuptbl[e->pnum] = e;
 	}
 
-	ubi_rb_for_each_entry(rb1, sv, &ai->volumes, rb) {
-		ubi_rb_for_each_entry(rb2, aeb, &sv->root, u.rb) {
+	ubi_rb_for_each_entry(rb1, av, &ai->volumes, rb) {
+		ubi_rb_for_each_entry(rb2, aeb, &av->root, u.rb) {
 			cond_resched();
 
 			e = kmem_cache_alloc(ubi_wl_entry_slab, GFP_KERNEL);