Patch out a fatal assertion in OpenMP runtime until preconditions are met

Compiling simple testcase with g++ and linking it to the LLVM OpenMP runtime
compiled in debug mode trips an assertion that produces a fatal error. When
the assertion is skipped, the program runs successfully to completion and 
produces the same answer as the sequential code. Intel will restore the
assertion with a patch that fixes the issues that cause it to trip.

Patch by John Mellor-Crummey

Differential Revision: http://reviews.llvm.org/D11269

llvm-svn: 243032