mm/rmap: rename anon_vma_unlock() => anon_vma_unlock_write()

The comment in commit 4fc3f1d66b1e ("mm/rmap, migration: Make
rmap_walk_anon() and try_to_unmap_anon() more scalable") says:

| Rename anon_vma_[un]lock() => anon_vma_[un]lock_write(),
| to make it clearer that it's an exclusive write-lock in
| that case - suggested by Rik van Riel.

But that commit renames only anon_vma_lock()

Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/mmap.c b/mm/mmap.c
index 28416f6..318e121 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -809,7 +809,7 @@
 		anon_vma_interval_tree_post_update_vma(vma);
 		if (adjust_next)
 			anon_vma_interval_tree_post_update_vma(next);
-		anon_vma_unlock(anon_vma);
+		anon_vma_unlock_write(anon_vma);
 	}
 	if (mapping)
 		mutex_unlock(&mapping->i_mmap_mutex);
@@ -3017,7 +3017,7 @@
 		if (!__test_and_clear_bit(0, (unsigned long *)
 					  &anon_vma->root->rb_root.rb_node))
 			BUG();
-		anon_vma_unlock(anon_vma);
+		anon_vma_unlock_write(anon_vma);
 	}
 }