We need to link with -lpthread now.
The CALLTARGETS workaround in our lit tests can be removed, since llvm-objdump has gotten more accurate than before with respect to symbols.
The -stats and -rng-seed options need to be renamed to avoid conflicting with the LLVM options being brought in.
BUG= https://code.google.com/p/nativeclient/issues/detail?id=3930
R=jvoung@chromium.org
Review URL: https://codereview.chromium.org/756543002
