usb: gadget: configfs: avoid spaces for indentation

This fixes the following checkpatch error:

ERROR: code indent should use tabs where possible

Here, spaces are replaced by a tab in 2 lines.
Signed-off-by: Parth Y Shah <sparth1292@gmail.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

drivers/usb/gadget/configfs.c

@@ -1217,8 +1217,8 @@ static void purge_configs_funcs(struct gadget_info *gi)
 			list_move_tail(&f->list, &cfg->func_list);
 			if (f->unbind) {
 				dev_dbg(&gi->cdev.gadget->dev,
-				         "unbind function '%s'/%p\n",
-				         f->name, f);
+					"unbind function '%s'/%p\n",
+					f->name, f);
 				f->unbind(c, f);
 			}
 		}