usb: gadget: function: printer: Fix a memory leak for interface descriptor

commit 2cc332e4ee4febcbb685e2962ad323fe4b3b750a upstream.

When printer driver is loaded, the printer_func_bind function is called, in
this function, the interface descriptor be allocated memory, if after that,
the error occurred, the interface descriptor memory need to be free.

Reviewed-by: Peter Chen <peter.chen@nxp.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Zqiang <qiang.zhang@windriver.com>
Link: https://lore.kernel.org/r/20201210020148.6691-1-qiang.zhang@windriver.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/gadget/function/f_printer.c b/drivers/usb/gadget/function/f_printer.c
index d89b304..b962f24 100644
--- a/drivers/usb/gadget/function/f_printer.c
+++ b/drivers/usb/gadget/function/f_printer.c
@@ -1120,6 +1120,7 @@
 		printer_req_free(dev->in_ep, req);
 	}
 
+	usb_free_all_descriptors(f);
 	return ret;
 
 }