board: gateworks: gw_ventana: convert to DM_I2C

convert to DM_I2C for U-Boot while leaving SPL legacy I2C:
 - Move I2C config from common to SPL
 - Move PMIC config from common to SPL (no need to re-configure pmic)
 - add DM_I2C support to eeprom/gsc functions shared by SPL and U-Boot

Signed-off-by: Tim Harvey <tharvey@gateworks.com>
10 files changed