i2c: designware: Add support to get I2C related timing parameters from firmware.

Similar to I2C designware platform driver add i2c_parse_fw_timings() in
PCI driver, to get I2C related timing parameters from firmware.

Signed-off-by: Sudarshan Ravula <sudarshan.ravula@intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>