[OPENMP]Delay emission of the error messages for the exceptions.

[OPENMP]Delay emission of the error messages for the exceptions.

Fixed diagnostic emission for the exceptions support in case of the
compilation of OpenMP code for the devices. From now on, it uses delayed
diagnostics mechanism, previously used for CUDA only. It allow to
diagnose not allowed used of exceptions only in functions that are going
to be codegen'ed.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@353542 91177308-0d34-0410-b5e6-96231b3b80d8