PNaCl: Add "not" to various test commands, to pass under LLVM 3.4

PNaCl: Add "not" to various test commands, to pass under LLVM 3.4

In LLVM 3.4, llvm-lit got stricter, so that the command "X | Y" is
treated as failing if X returns a non-zero exit status.  (llvm-lit
sets "pipefail" in Bash.)  The way to fix this is to write "not X | Y"
instead.

Mostly fixed with:

perl -pi -e 's/RUN: pnacl-abicheck/RUN: not pnacl-abicheck/' $(git ls-files test/NaCl/PNaClABI/)

BUG=https://code.google.com/p/nativeclient/issues/detail?id=3757
TEST=tested with LLVM 3.4 merged
R=dschuff@chromium.org

Committed: https://gerrit.chromium.org/gerrit/gitweb?p=native_client/pnacl-llvm.git;a=commit;h=803421a

[Derek Schuff, 2014-01-21 18:33:51]

lgtm

[Mark Seaborn, 2014-01-21 18:37:00]

Committed patchset #1 manually as r803421a (presubmit successful).