leds: leds-cros_ec: Avoid -Wflex-array-member-not-at-end warning

-Wflex-array-member-not-at-end was introduced in GCC-14, and we are
getting ready to enable it, globally.

Replace an on-stack definition of a flexible structure with a call
to utility function cros_ec_cmd().

So, with these changes, fix the following warning:

drivers/leds/leds-cros_ec.c:70:40: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end]

Signed-off-by: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Acked-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://lore.kernel.org/r/Z-rKcgFjsyKvd58q@kspp
Signed-off-by: Lee Jones <lee@kernel.org>

Author: GustavoARSilva

drivers/leds/leds-cros_ec.c

@@ -60,31 +60,18 @@ static inline struct cros_ec_led_priv *cros_ec_led_cdev_to_priv(struct led_class
 union cros_ec_led_cmd_data {
 	struct ec_params_led_control req;
 	struct ec_response_led_control resp;
-} __packed;
+};
 
 static int cros_ec_led_send_cmd(struct cros_ec_device *cros_ec,
 				union cros_ec_led_cmd_data *arg)
 {
 	int ret;
-	struct {
-		struct cros_ec_command msg;
-		union cros_ec_led_cmd_data data;
-	} __packed buf = {
-		.msg = {
-			.version = 1,
-			.command = EC_CMD_LED_CONTROL,
-			.insize  = sizeof(arg->resp),
-			.outsize = sizeof(arg->req),
-		},
-		.data.req = arg->req
-	};
-
-	ret = cros_ec_cmd_xfer_status(cros_ec, &buf.msg);
+
+	ret = cros_ec_cmd(cros_ec, 1, EC_CMD_LED_CONTROL, &arg->req,
+			  sizeof(arg->req), &arg->resp, sizeof(arg->resp));
 	if (ret < 0)
 		return ret;
 
-	arg->resp = buf.data.resp;
-
 	return 0;
 }