app/test: fix missing NULL pointer checks
app/test: fix missing NULL pointer checks

In test_sched, we are missing NULL pointer checks after create_mempool()
and rte_pktmbuf_alloc(). Add in these checks using TEST_ASSERT_NOT_NULL macros.

VERIFY macro was removed and replaced by standard test ASSERTS from "test.h" header.
This provides additional information to track when the failure occurred.

Signed-off-by: Daniel Mrzyglod <998f22cc3a6ac3535545292178d834b83a4e2a87@intel.com>

tsphillips/dpdk-fork,venkynv/dpdk-mirror,msune/dpdk,mixja/dpdk,venkynv/dpdk-mirror,john-mcnamara-intel/dpdk,mixja/dpdk,john-mcnamara-intel/dpdk,msune/dpdk,venkynv/dpdk-mirror,tsphillips/dpdk-fork,tsphillips/dpdk-fork,mixja/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,msune/dpdk,venkynv/dpdk-mirror,mixja/dpdk,tsphillips/dpdk-fork,msune/dpdk