QPID-4582, QPID-5215: fix linking errors for clock_gettime

git-svn-id: https://svn.apache.org/repos/asf/qpid/trunk@1532408 13f79535-47bb-0310-9956-ffa450edef68
QPID-5236: correct symbolic descriptor for amqp value section

git-svn-id: https://svn.apache.org/repos/asf/qpid/trunk@1532409 13f79535-47bb-0310-9956-ffa450edef68