[asan] [SystemZ] Add slop for stack address detection.
[asan] [SystemZ] Add slop for stack address detection.

On s390, siginfo reports the faulting address with page granularity -
we need to mask off the low bits of sp before comparison.

Differential Revision: http://reviews.llvm.org/D19112

git-svn-id: c199f293c43da69278bea8e88f92242bf3aa95f7@266593 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