i2c: qcom-geni: add support for I2C Master Hub variant

The I2C Master Hub is a stripped down version of the GENI Serial Engine
QUP Wrapper Controller but only supporting I2C serial engines without
DMA support.

Add the I2C Master Hub serial engine compatible along the specific
requirements in a new desc struct passed through the device match data.

Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>