Split i2c.c code in two (i2c_slave.c and i2c_master.c). i2c_slave.c is
used when EC has no i2c device connected (i2c master code not needed)
but EC is connected to AP via i2c.
BRANCH=none
BUG=b:37584134
TEST=1. Compile rose board with CONFIG_I2C and CONFIG_CMD_HOSTCMD. Then
make sure EC_CMD_GET_PROTOCOL_INFO works.
2. On Kevin and Elm, cherry-pick to firmware branch respectively,
build and flash ec, i2c function works.
Change-Id: I1f95ad277713c5e30913e0a010ca03dfd9ec248c
Signed-off-by: Wei-Ning Huang <wnhuang@google.com>
Reviewed-on: https://chromium-review.googlesource.com/484999
Commit-Ready: Wei-Ning Huang <wnhuang@chromium.org>
Tested-by: Wei-Ning Huang <wnhuang@chromium.org>
Reviewed-by: Vincent Palatin <vpalatin@chromium.org>
