[scudo] getauxval alternative for Android
[scudo] getauxval alternative for Android

Summary:
`getauxval` was introduced with API level 18. In order to get things to work
at lower API levels (for the toolchain itself which is built at 14 for 32-bit),
we introduce an alternative implementation reading directly from
`/proc/self/auxv`.

Reviewers: alekseyshl

Reviewed By: alekseyshl

Subscribers: srhines, llvm-commits

Differential Revision: https://reviews.llvm.org/D37488

git-svn-id: c199f293c43da69278bea8e88f92242bf3aa95f7@312653 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/compiler-rt,llvm-mirror/compiler-rt,llvm-mirror/compiler-rt,llvm-mirror/compiler-rt,llvm-mirror/compiler-rt