i2c: iproc: add support for SMBUS quick cmd

Add support for SMBUS quick command.

SMBUS quick command passes single bit of information to the
slave (target) device. Can be used to turn slave device on or off.

By default i2c_detect tool uses the smbus quick cmd to try and
detect devices. Without this support it will not detect some slaves.

Signed-off-by: Rayagonda Kokatanur <rayagonda.kokatanur@broadcom.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>