arm: socfpga: vining: Enable DW I2C driver

The Designware I2C IP is used to communicate with I2C peripherals on
SoCFPGA, and required to access I2C EEPROM on this board. Enable it.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Siew Chin Lim <elly.siew.chin.lim@intel.com>
Cc: Simon Goldschmidt <simon.k.r.goldschmidt@gmail.com>
Cc: Tien Fong Chee <tien.fong.chee@intel.com>