driver: brcm: add i2c driver

Broadcom I2C controller driver. Follwoing API's are supported:-
- i2c_init() Intialize ethe I2C controller
- i2c_probe()
- i2c_set_bus_speed() Set the I2C bus speed
- i2c_get_bus_speed() Get the current bus speed
- i2c_recv_byte() Receive one byte of data.
- i2c_send_byte() Send one byteof data
- i2c_read_byte() Read single byte of data
- i2c_read() Read multiple bytes of data
- i2c_write_byte Write single byte of data
- i2c_write() Write multiple bytes of data

This driver is verified by reading the DDR SPD data.

Signed-off-by: Bharat Gooty <bharat.gooty@broadcom.com>
Change-Id: I2d7fe53950e8b12fab19d0293020523ff8b74e13
4 files changed