Add a driver for DesignWare I2C controller IP block found on several
SoCs including Altera SoC products
Tested using Terrasic SoCKit board and GPIO expander board with I2C
EEPROM on it
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>