i2c: New-style EEPROM driver using device IDs

Add a new-style driver for most I2C EEPROMs, giving sysfs read/write
access to their data. Tested with various chips and clock rates.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Jean Delvare <khali@linux-fr.org>