btrfs: remove unused fs_info arg from btrfs_close_extra_devices()

The commit:
8dabb74 Btrfs: change core code of btrfs to support the
        device replace operations
added the fs_info argument, but never used it -
just remove it again.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 6911aa4..d91f089 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -2690,7 +2690,7 @@
 	 * keep the device that is marked to be the target device for the
 	 * dev_replace procedure
 	 */
-	btrfs_close_extra_devices(fs_info, fs_devices, 0);
+	btrfs_close_extra_devices(fs_devices, 0);
 
 	if (!fs_devices->latest_bdev) {
 		printk(KERN_ERR "BTRFS: failed to read devices on %s\n",
@@ -2794,7 +2794,7 @@
 		goto fail_block_groups;
 	}
 
-	btrfs_close_extra_devices(fs_info, fs_devices, 1);
+	btrfs_close_extra_devices(fs_devices, 1);
 
 	ret = btrfs_sysfs_add_one(fs_info);
 	if (ret) {