i2c: Add cadence iic driver

This IP is found in Xilinx SoC, it only been tested on ZynqMP (arm64)
so only enable it there for now.

Differential Revision: https://reviews.freebsd.org/D41994

(cherry picked from commit 137b58e4d2044adc200d13c8989d3746a0a4bd7f)