misc: (at24) move header to linux/platform_data/

This patch moves the at24.h header from include/linux/i2c to
include/linux/platform_data and updates existing support accordingly.

It also fixes the following checkpatch warning:

    WARNING: please, no space before tabs
    #436: FILE: include/linux/platform_data/at24.h:31:
    + * ^Iu8 *mac_addr = ethernet_pdata->mac_addr;$

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
diff --git a/drivers/misc/eeprom/at24.c b/drivers/misc/eeprom/at24.c
index 5d4fd69..4ef01ab 100644
--- a/drivers/misc/eeprom/at24.c
+++ b/drivers/misc/eeprom/at24.c
@@ -22,7 +22,7 @@
 #include <linux/jiffies.h>
 #include <linux/of.h>
 #include <linux/i2c.h>
-#include <linux/i2c/at24.h>
+#include <linux/platform_data/at24.h>
 
 /*
  * I2C EEPROMs from most vendors are inexpensive and mostly interchangeable.