service: initialize with EAL

service: initialize with EAL

This commit shows the changes required in rte_eal_init()
to transparently launch the service threads. The threads
are launched into the service worker functions here because
after rte_eal_init() the application is not gauranteed to
call any other DPDK API.

As the registration of services happens at initialization
time, the services that require CPU time are already available
when we reach the end of rte_eal_init().

Signed-off-by: Harry van Haaren <harry.van.haaren@intel.com>
Acked-by: Jerin Jacob <jerin.jacob@caviumnetworks.com>