Fix DoS vulnerability in DHO_OPTIONSOVERLOADED.

Bug: 16677003
Change-Id: I6ac3318c04fa99d964e15aa2f06a5794daf61c7e
Suppress warning on comparing array with null.

BUG: 17356808
Change-Id: Iecd7c9407e388530a098681fcedb8f18c2ba5b38
Merge "Suppress warning on comparing array with null."
Merge "Fix DoS vulnerability in DHO_OPTIONSOVERLOADED."
Move check of IFF_LOWER_UP after all includes.

The latest uapi kernel headers use an enum for values such as
IFF_LOWER_UP. This code defines IFF_LOWER_UP and causes the inclusion
of if.h later on to mess up the enum definition.

Move the IFF_LOWER_UP check after all of the includes.

Change-Id: I9d9ce63a63bb6fc82a2424776f5aa6700cc34239
Merge "Move check of IFF_LOWER_UP after all includes."