i2c: Add Zhaoxin I2C driver

zhaoxin inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I6J3EV


CVE: NA

--------------------------------------------

Zhaoxin I2C Linux driver support all bidirectional bus protocols speed
specified in the I2C Specification 7.0. The speed mode listed in the
followed table.

|   Speed Name    |           Description                |
| Standard-mode   | Bit rate up to 100 kbit/s            |
| Fast-mode       | Bit rate up to 400 kbit/s.(default)  |
| Fast-mode Plus  | Bit rate up to 1 Mbit/s              |
| High-speed mode | Bit rate up to 3.4 Mbit/s.           |

Signed-off-by: leoliu-oc <leoliu-oc@zhaoxin.com>