mempool: notify memory area to pool

mempool: notify memory area to pool

HW pool manager e.g. Octeontx SoC demands s/w to program start and end
address of pool. Currently, there is no such api in external mempool.
Introducing rte_mempool_ops_register_memory_area api which will let HW(pool
manager) to know when common layer selects hugepage:
For each hugepage - Notify its start/end address to HW pool manager.

Signed-off-by: Santosh Shukla <santosh.shukla@caviumnetworks.com>
Signed-off-by: Jerin Jacob <jerin.jacob@caviumnetworks.com>
Acked-by: Olivier Matz <olivier.matz@6wind.com>