am 68ffdee6: Merge "Update to v3.18.21 kernel headers."

* commit '68ffdee696b57b63fce2753508662a920ad71b11':
  Update to v3.18.21 kernel headers.
tree: 685d9838ccf730135c9dca8eeecd38e631486277
  1. original/
  2. CleanSpec.mk
  3. MODULE_LICENSE_GPL
  4. NOTICE