board: gateworks: venice: update GW74xx PMIC config

board: gateworks: venice: update GW74xx PMIC config

Update the GW74xx PMIC configuration:
 - increase VDD_SOC DVS1 to 0.85V per datasheet
 - increase VDD_SOC DVS0 to 0.95V before first DRAM access
 - increase VDD_ARM DVS0 to 0.95V to support kernel overdrive voltage (OD)
 - remove unnecessary changes to VDD_DRAM as we don't use 3GHz DRAM
 - remove unnecessary change to LDO2 as it is unused

Signed-off-by: Tim Harvey <tharvey@gateworks.com>
v2: update commit log with more detail