[msandr] Add support for standalone test.

Add macro MSANDR_STANDALONE_TEST for standalone test without msan executables.

Patch by Qin Zhao.


git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@193643 91177308-0d34-0410-b5e6-96231b3b80d8
[sanitizer] Intercept sincos, remquo, lgamma, lgamma_r.


git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@193645 91177308-0d34-0410-b5e6-96231b3b80d8