app/testpmd: fix build for IBM Power
app/testpmd: fix build for IBM Power

This patch fixes compiling problems on IBM Power architecture and turn
on the test-pmd compiling option in configuration file. Actually, this
is an big endian compiling fix.

Signed-off-by: Chao Zhu <fb95c043d5fa3fcf28eb07d8ee8ac9e1289ed03b@linux.vnet.ibm.com>
Acked-by: David Marchand <f28529695cfa9e3e1eb84e7072aa626af4abb18e@6wind.com>

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