cmake LAGRAPH_HAS_OPENMP examples

GraphBLAS/LAGraph CMakeLists.txt :191

message ( STATUS "LAGraph has OpenMP: ${LAGRAPH_HAS_OPENMP}" )

jlblancoc/suitesparse-metis-for-windows SuiteSparse/LAGraph/CMakeLists.txt :192

message ( STATUS "LAGraph has OpenMP: ${LAGRAPH_HAS_OPENMP}" )

DrTimothyAldenDavis/SuiteSparse LAGraph/CMakeLists.txt :191

message ( STATUS "LAGraph has OpenMP: ${LAGRAPH_HAS_OPENMP}" )