Merging r182645:

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r182645 | eugenis | 2013-05-24 07:28:03 -0700 (Fri, 24 May 2013) | 6 lines

Add -lrt to sanitizer link arguments.

Sanitizer runtime intercepts functions from librt. Not doing this will fail
if the librt dependency is not present at program startup (ex. comes from a
dlopen()ed library).

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llvm-svn: 182944