[TSan] kill some linux-specific code in favor of code in common runtime: reuse wrappers for mmap routines, ProcessMaps iterator, thread stack calculation

llvm-svn: 158657

llvm-svn: 158655

llvm-svn: 158502

llvm-svn: 158499

llvm-svn: 158496

[Sanitizer] move more portability wrappers to common runtime: sleep, _exit, abort, atexit, pthread_self

llvm-svn: 158493

llvm-svn: 158490

llvm-svn: 158452

llvm-svn: 158078

llvm-svn: 158056

llvm-svn: 158001

[Sanitizer] add sanitizer_posix.cc. Move more various functions into sanitizer_libc: sscanf, munmap, memchr

llvm-svn: 157994