ext4: fix build error when DX_DEBUG is defined

Enabling DX_DEBUG triggers the build error below.  info is an attribute
of  the dxroot structure.

linux/fs/ext4/namei.c:2264:12: error: ‘info’
undeclared (first use in this function); did you mean ‘insl’?
	   	  info->indirect_levels));

Fixes: e08ac99f ("ext4: add largedir feature")
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.co.uk>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Lukas Czerner <lczerner@redhat.com>

fs/ext4/namei.c

@@ -2261,7 +2261,7 @@ static int ext4_dx_add_entry(handle_t *handle, struct ext4_filename *fname,
 			dxroot->info.indirect_levels += 1;
 			dxtrace(printk(KERN_DEBUG
 				       "Creating %d level index...\n",
-				       info->indirect_levels));
+				       dxroot->info.indirect_levels));
 			err = ext4_handle_dirty_dx_node(handle, dir, frame->bh);
 			if (err)
 				goto journal_error;