mempool: fix typos
mempool: fix typos

Signed-off-by: Andriy Berestovskyy <5a0adb12ae95814153dc6089b3d01dffbbe8369c@caviumnetworks.com>
Acked-by: Olivier Matz <dfcc1510895413197abb4336e39bb0a3906cba71@6wind.com>

john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk