staging: rtl8712: style fix multiple line dereference

It fix the following checkpatch.pl warning:
Avoid multiple line dereference - prefer %s
Suggested-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Moon Yeounsu <yyyynoom@gmail.com>
Link: https://lore.kernel.org/r/20240721040504.1483-1-yyyynoom@gmail.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/rtl8712/rtl871x_cmd.c

@@ -528,8 +528,9 @@ void r8712_setstakey_cmd(struct _adapter *padapter, u8 *psta, u8 unicast_key)
 	if (unicast_key)
 		memcpy(&psetstakey_para->key, &sta->x_UncstKey, 16);
 	else
-		memcpy(&psetstakey_para->key, &psecuritypriv->XGrpKey[psecuritypriv->XGrpKeyid - 1].
-		       skey, 16);
+		memcpy(&psetstakey_para->key,
+		       &psecuritypriv->XGrpKey[psecuritypriv->XGrpKeyid - 1].skey,
+		       16);
 	r8712_enqueue_cmd(pcmdpriv, ph2c);
 }