grove/lcd: add an option to specify I2C master

Add an option to specify to which I2C master the Grove LCD
is connected, instead of already using the i2c_dw driver
port #0.

Change-Id: I4e61ef8e31c75ae912e2d16f8939369c0b8bbc2c
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
2 files changed