i2c: Delete the broken i2c-ite bus driver

The rest of the ITE8172 support was already removed from MIPS tree.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Acked-by: Ralf Baechle <ralf@linux-mips.org>