cmake HAVE_PRLIMIT examples

mysql/mysql-router cmake/configure.cmake :253 

check_symbol_exists(prlimit sys/resource.h HAVE_PRLIMIT)

polardb/polardbx-engine router/cmake/configure.cmake :134 

check_symbol_exists(prlimit sys/resource.h HAVE_PRLIMIT)

GreatSQL/GreatSQL router/cmake/configure.cmake :134 

check_symbol_exists(prlimit sys/resource.h HAVE_PRLIMIT)

facebook/mysql-5.6 router/cmake/configure.cmake :134 

check_symbol_exists(prlimit sys/resource.h HAVE_PRLIMIT)