Merge branch 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa...

Pull i2c fixes from Wolfram Sang:
 "Two bugfixes, one v4.16 regression fix, and two documentation fixes"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: designware: Consider SCL GPIO optional
  i2c: busses: i2c-sirf: Fix spelling: "formular" -> "formula".
  i2c: bcm2835: Set up the rising/falling edge delays
  i2c: i801: Add missing documentation entries for Braswell and Kaby Lake
  i2c: designware: must wait for enable