ig4 - Recognize Haswell, the Atom SoCs and Skylake/Kaby Lake accordingly.

ig4 - Recognize Haswell, the Atom SoCs and Skylake/Kaby Lake accordingly.

* Some of the registers only exist in some of Intel's i2c controller
  versions, and some registers have different locations or content.

* This should make ig4 attach successfully on Skylake-U/Y and Kaby Lake-U/Y.