eal: initialize lcore and socket id

eal: initialize lcore and socket id

Set _lcore_id and _socket_id to (-1) by default.
For those non EAL thread, _lcore_id shall always be LCORE_ID_ANY.
The libraries using _lcore_id as index need to take care.
_socket_id always be SOCKET_ID_ANY until the thread changes the affinity
by rte_thread_set_affinity().

Signed-off-by: Cunming Liang <cunming.liang@intel.com>
Acked-by: Olivier Matz <olivier.matz@6wind.com>
Acked-by: Konstantin Ananyev <konstantin.ananyev@intel.com>