Wangxun 10Gb ethernet chip is connected to Designware I2C, to communicate
with SFP.

Introduce the property "wx,i2c-snps-model" to match device data for Wangxun
in software node case. Since IO resource was mapped on the ethernet driver,
add a model quirk to get regmap from parent device.

The exists IP limitations are dealt as workarounds:
- IP does not support interrupt mode, it works on polling mode.
- Additionally set FIFO depth address the chip issue.
Signed-off-by: Jiawen Wu <jiawenwu@trustnetic.com>
Reviewed-by: Piotr Raczynski <piotr.raczynski@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>