include kernel.h instead of zephyr.h

- zephyr.h is already deprecated, hence using kernel.h instead of it.
- fix zephyrproject-rtos#47
- affects cores/ and variants/ dirs

Signed-off-by: Dhruva Gole <goledhruva@gmail.com>

Author: DhruvaG2000

cores/arduino/Arduino.h

@@ -7,7 +7,7 @@
 #include "api/ArduinoAPI.h"
 
 #include <zephyr/drivers/gpio.h>
-#include <zephyr/zephyr.h>
+#include <zephyr/kernel.h>
 
 #include <variants.h>
-#include <zephyrSerial.h>
+#include <zephyrSerial.h>

variants/arduino_nano_33_ble/arduino_nano_33_ble_pinmap.h

@@ -7,7 +7,7 @@
 /* All the pins that are 100 + x are gpio1 pins and < 100 are in gpio0 */
 #pragma once
 #include <zephyr/drivers/gpio.h>
-#include <zephyr/zephyr.h>
+#include <zephyr/kernel.h>
 #include <zephyr/drivers/i2c.h>
 #include <zephyr/device.h>
 

variants/arduino_nano_33_ble_sense/arduino_nano_33_ble_sense_pinmap.h

@@ -7,7 +7,7 @@
 /* All the pins that are 100 + x are gpio1 pins and < 100 are in gpio0 */
 #pragma once
 #include <zephyr/drivers/gpio.h>
-#include <zephyr/zephyr.h>
+#include <zephyr/kernel.h>
 #include <zephyr/drivers/i2c.h>
 #include <zephyr/device.h>
 

variants/arduino_nano_33_iot/arduino_nano_33_iot_pinmap.h

@@ -7,7 +7,7 @@
 /* All the pins that are 100 + x are gpio1 pins and < 100 are in gpio0 */
 #pragma once
 #include <zephyr/drivers/gpio.h>
-#include <zephyr/zephyr.h>
+#include <zephyr/kernel.h>
 #include <zephyr/drivers/i2c.h>
 #include <zephyr/device.h>
 

variants/nrf52840dk_nrf52840/nrf52840dk_nrf52840_pinmap.h

@@ -9,7 +9,7 @@
 
 #include <zephyr/drivers/gpio.h>
 #include <zephyr/drivers/i2c.h>
-#include <zephyr/zephyr.h>
+#include <zephyr/kernel.h>
 
 #define LED_BUILTIN 22