maintainers: update for IBM POWER
maintainers: update for IBM POWER

Succeed Chao Zhu as maintainer of EAL for IBM POWER.

Cc: stable@dpdk.org

Signed-off-by: David Christensen <9a876b0e626a7e524926f129e2e0ea9c4c104ff4@linux.vnet.ibm.com>
Acked-by: Chao Zhu <fb95c043d5fa3fcf28eb07d8ee8ac9e1289ed03b@linux.vnet.ibm.com>

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