i2c: i2c-boardinfo: sort includes

I request this for drivers, so the core should adhere to sorted includes as
well.

Signed-off-by: Wolfram Sang <[e-mail]>

drivers/i2c/i2c-boardinfo.c

···
  * GNU General Public License for more details.
  */
 
-#include <linux/kernel.h>
-#include <linux/i2c.h>
-#include <linux/slab.h>
 #include <linux/export.h>
+#include <linux/i2c.h>
+#include <linux/kernel.h>
 #include <linux/rwsem.h>
+#include <linux/slab.h>
 
 #include "i2c-core.h"