1. Start function: Issue repeat start when bus is busy
2. Byte write function: Do not call SDK function as this does
not work for some of the Kinetis device
3. Byte read function: Do not call SDK function as this would
issue a START and STOP signal which is not required for
I2C byte functions
Signed-off-by: Mahesh Mahadevan <mahesh.mahadevan@nxp.com>