usb: chipidea: udc: Use the preferred form for passing a size of a struct

According to Documentation/CodingStyle:

"The preferred form for passing a size of a struct is the following:

	p = kmalloc(sizeof(*p), ...);
"
, so do as suggested to improve readability.
Signed-off-by: NFabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: NPeter Chen <peter.chen@nxp.com>

drivers/usb/chipidea/udc.c

@@ -1993,7 +1993,7 @@ int ci_hdrc_gadget_init(struct ci_hdrc *ci)
 	if (!hw_read(ci, CAP_DCCPARAMS, DCCPARAMS_DC))
 		return -ENXIO;
 
-	rdrv = devm_kzalloc(ci->dev, sizeof(struct ci_role_driver), GFP_KERNEL);
+	rdrv = devm_kzalloc(ci->dev, sizeof(*rdrv), GFP_KERNEL);
 	if (!rdrv)
 		return -ENOMEM;