ec/google/wilco: Enable WiFi radio

Add EC command to enable WiFi radio and send that command at
startup.  Tested to ensure WiFi is functional on a sarien board.

Change-Id: Iac46895c7118567e1eb55ea33051a1662103b563
Signed-off-by: Duncan Laurie <dlaurie@google.com>
Reviewed-on: https://review.coreboot.org/c/29673
Reviewed-by: Furquan Shaikh <furquan@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/ec/google/wilco/commands.c

@@ -149,3 +149,12 @@ void wilco_ec_power_off(enum ec_power_off_reason reason)
 			     KB_POWER_OFF, &reason, 1, NULL, 0) < 0)
 		printk(BIOS_ERR, "%s: command failed\n", __func__);
 }
+
+int wilco_ec_radio_control(enum ec_radio radio, uint8_t state)
+{
+	uint8_t radio_control[3] = { 0, radio, state };
+
+	return wilco_ec_mailbox(WILCO_EC_MSG_DEFAULT, KB_RADIO_CONTROL,
+				radio_control, ARRAY_SIZE(radio_control),
+				NULL, 0);
+}