mman.h: Add missing MADV_XXX defines. am: 5041589cec am: d6445f8d9f

Original change: https://android-review.googlesource.com/c/platform/prebuilts/gcc/linux-x86/host/x86_64-linux-glibc2.17-4.8/+/2901535

Change-Id: Ide9cfcd1df5695973a8f689dfbe9da5e20841840
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>