[asan] Disable thread-safe static initilization with VS 2015
[asan] Disable thread-safe static initilization with VS 2015

ASan interceptors contain local statics which run before the CRT is
initialized. Thread-safe statics appear to rely on CRT-internal state,
and will crash without this flag.

git-svn-id: c199f293c43da69278bea8e88f92242bf3aa95f7@263979 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