cheza: Lower the I2C bus speed of smart battery
cheza: Lower the I2C bus speed of smart battery

The I2C speed of the smart battery is 100KHz. Lower the bus speed.

BRANCH=none
BUG=b:74395451
TEST=Used console command "i2cscan" to check the smart battery.

Change-Id: I3f5f1e7ac1707ba416036214afa2ff46dad7f174
Signed-off-by: Tom Wai-Hong Tam <04b587fdf5845741a0c5a8b9cd59ca72d73ef8fc@google.com>
Reviewed-on: https://chromium-review.googlesource.com/1040874
Commit-Ready: Wai-Hong Tam <04b587fdf5845741a0c5a8b9cd59ca72d73ef8fc@google.com>
Tested-by: Wai-Hong Tam <04b587fdf5845741a0c5a8b9cd59ca72d73ef8fc@google.com>
Reviewed-by: Vincent Palatin <70a9964ec8fd10b0b08fcc8623c2add25ddf99ac@chromium.org>

coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec