pinctrl: moorefield: Replace kernel.h by what is actually being used

The kernel.h is a mess of unrelated things and we only used it
as a proxy to array_size.h, hence switch from former to the latter.

Signed-off-by: Andy Shevchenko <[e-mail]>

drivers/pinctrl/intel/pinctrl-moorefield.c

···
  * Author: Andy Shevchenko <[e-mail]>
  */
 
+#include <linux/array_size.h>
 #include <linux/init.h>
-#include <linux/kernel.h>
 #include <linux/mod_devicetable.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>