hikey-kernel: Update prebuilt kernel to 4.4.8 (956a9dd)
am: 78e2e21bb4

* commit '78e2e21bb4a9857a2be5b7021fef7f3c4c0baa99':
  hikey-kernel: Update prebuilt kernel to 4.4.8 (956a9dd)

Change-Id: I71f2cd828472462c49819a50ecb72e9da896efb3