[sanitizer] Add interceptors for readlinkat, name_to_handle_at, open_by_handle_at

Summary:
Also move existing readlink msan interceptor to sanitizer_common.

Fixes google/sanitizers#908

Patch by Oliver Chang

Reviewers: vitalybuka, eugenis

Reviewed By: vitalybuka

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D42630

llvm-svn: 323825