cmake BSON_HAVE_TIMESPEC examples

cvet/fonline ThirdParty/mongo-c-driver/src/libbson/CMakeLists.txt :90 

check_struct_has_member ("struct timespec" tv_sec time.h BSON_HAVE_TIMESPEC)

realm/realm-core src/external/bson/CMakeLists.txt :34 

CHECK_STRUCT_HAS_MEMBER ("struct timespec" tv_sec time.h BSON_HAVE_TIMESPEC)