Added audit.h from the kernel.

Just followed the recipe in I1ca996541d05b0d5927ab828a6ce49c09877ea01

Change-Id: I5713d9ce5ff62e310a694ecfbe21cad6577bcb4d
Merge branch 'cm-10.1' of git://github.com/CyanogenMod/android_bionic into cm-10.1