LTSI-v4.14 Backport or I2C R-Car Fix

Base:
* v4.14.61
* Backports of components for Renesas SoCs to v4.18

Backport of post-v4.18 fix for i2c-rcar:
* implement STOP and REP_START according to docs

Dependency of above
* Refactor private flags of i2c-rcar driver
Merge tag 'backport/v4.14.40/i2c-rcar-selected-to-next-20180821' into backport/v4.14.61/snapshot