Fix vdd_log to support a new Micron DDR4

I tested:

• It can boot Manjaro
• It appears to set vdd_log to max 1V
• It can boot my Ubuntu when SDcard is inserted

What was not tested:

• If it works with all possible RAMs
• If it works with Android SDCard

Log

U-Boot 2017.09-03642-g183e247f90-dirty (May 01 2021 - 20:18:12 +0200)

Model: Pine64 RK3399 Pinebook Pro
DRAM:  3.9 GiB
Sysmem: init 
Relocation Offset is: f5bf0000
I2c0 speed: 400000Hz
PMIC:  RK808 
vdd_center 900000 uV
vdd_log init 900000 uV
rk_board_init PWM2 pinctrl init fail!
rk_board_init: vcc3v0_sdio cannot set regulator value -38
vdd_center 900000 uV
                DCDC_REG1@     vdd_center:  750000uV <-> 1400000uV, set  900000uV, enabling | suspend     -61uV, disabled
                DCDC_REG4@        vcc_1v8: 1800000uV <-> 1800000uV, set 1800000uV, enabling | suspend 1800000uV, enabling
                 LDO_REG1@     vcc1v8_dvp: 1800000uV <-> 1800000uV, set 1800000uV, enabling | suspend 1800000uV, enabling
                 LDO_REG4@         vcc_sd: 3300000uV <-> 3300000uV, set 3300000uV, enabling | suspend 3300000uV, enabling
                 LDO_REG7@  vcca1v8_codec: 1800000uV <-> 1800000uV, set 1800000uV, enabling | suspend 1800000uV, enabling
                 LDO_REG8@        vcc_3v0: 3000000uV <-> 3000000uV, set 3000000uV, enabling | suspend 3000000uV, enabling
              SWITCH_REG2@      vcc3v3_s0:     -61uV <->     -61uV, set       0uV, enabling | suspend     -61uV, disabled
                   dc-12v@         dc_12v: 12000000uV <-> 12000000uV, set 12000000uV, enabling | suspend     -61uV, enabling (ret: -38)
                  vcc-sys@        vcc_sys: 5000000uV <-> 5000000uV, set 5000000uV, enabling | suspend     -61uV, enabling (ret: -38)
               vcc3v3-sys@     vcc3v3_sys: 3300000uV <-> 3300000uV, set 3300000uV, enabling | suspend     -61uV, enabling (ret: -38)
        vcc-phy-regulator@        vcc_phy:     -61uV <->     -61uV, set     -61uV, enabling | suspend     -61uV, enabling
            led-regulator@  led_regulator:     -61uV <->     -61uV, set     -61uV, enabling | suspend     -61uV, enabling
           vcc5v0-host-en@    vcc5v0_host: 5000000uV <-> 5000000uV, set 5000000uV, enabling | suspend     -61uV, enabling (ret: -38)
vcc5v0-usb3-host-regulator@vcc5v0_usb3_host:     -61uV <->     -61uV, set     -61uV, enabling | suspend     -61uV, enabling
         vcc5v0-typec0-en@  vcc5v0_typec0:     -61uV <->     -61uV, set     -61uV, enabling | suspend     -61uV, enabling
              vcc1v8-sdio@    vcc1v8_sdio: 1800000uV <-> 1800000uV, set 1800000uV, enabling | suspend     -61uV, enabling (ret: -38)
              vcc3v0-sdio@    vcc3v0_sdio: 3000000uV <-> 3000000uV, set 3000000uV, enabling | suspend     -61uV, enabling ; init 3000000uV (ret: -38)
vdd_log init 900000 uV
                  vdd_log@        vdd_log:  800000uV <-> 1000000uV, set  900000uV, enabling | suspend     -61uV, enabling ; init  900000uV
MMC:   dwmmc@fe310000: 2, sdhci@fe330000: 0, dwmmc@fe320000: 1
Invalid bus 0 (err=-19)
*** Warning - spi_flash_probe_bus_cs() failed, using default environment

In:    serial
Out:   serial