Fix for testsuite including omp.h

When calling the testsuite, clang could not locate omp.h.  The
proper environment variable was modified to include:
exports/common/omp.h.  Documentation was also updated to be more
clear.

Patch by Sunita Chandrasekaran

llvm-svn: 237618

openmp/runtime/Makefile

@@ -61,6 +61,7 @@ test: omp
         if [ -d "$(omp_root)$(SLASH)..$(SLASH)testsuite$(SLASH)LLVM-IR" ] ; then \
 			export TESTSUITE_TEMP=$(realpath $(omp_root))$(SLASH)tmp ; \
 			export LIBRARY_PATH=$(libiomp5_path):$(LIBRARY_PATH) ; \
+			export INCLUDE_PATH=$(libiomp5_path)$(SLASH)..$(SLASH)..$(SLASH)common$(CLASH)include:$(INCLUDE_PATH) ; \
 			export LD_LIBRARY_PATH=$(libiomp5_path):$(LD_LIBRARY_PATH) ; \
 			export DYLD_LIBRARY_PATH=$(libiomp5_path):$(DYLD_LIBRARY_PATH) ; \
 			cd $(omp_root)$(SLASH)..$(SLASH)testsuite ; \

openmp/testsuite/README_LLVM_OPENMP

@@ -8,7 +8,7 @@
 
 Two new files have been added to openmp/runtime: check-openmp.pl and check-openmp-test.pl 
 Go to /openmp/runtime, run:
-make test
+make test compiler=clang
 make test-clean  
 
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