i2c: hix5hd2: Add I2C_M_STOP flag support for i2c-hix5hd2 driver.

For compatibility, some devices need to work with controller between
messages using a stop.

Signed-off-by: taolan <taolan@huawei.com>
Acked-by: Andi Shyti <andi.shyti@kernel.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>