This patch allows to pass the OpenMP runtime tests after configuring with
`cmake . -DOPENMP_TEST_FLAGS:STRING="-Werror"`.
The warnings for OMPT tests are addressed in D90752.
Differential Revision: https://reviews.llvm.org/D91280
Current parsing allows trailing string after the permitted value,
MANDATORY|DISABLED|DEFAULT -- e.g., "mandatorynot" is also recognized
as "MANDATORY". Such cases should be recognized as incorrect/unknown
value.
Differential Revision: https://reviews.llvm.org/D62431
llvm-svn: 362125