test/service: check active state on two lcores

test/service: check active state on two lcores

The test checks that the service may be active API works
when there are two cores: a non-service lcore and a service one.

The API notes to take care when checking the status of a running
service, but the test setup allows for a safe usage in that case.

Signed-off-by: Igor Romanov <igor.romanov@oktetlabs.ru>
Signed-off-by: Andrew Rybchenko <arybchenko@solarflare.com>
Acked-by: Harry van Haaren <harry.van.haaren@intel.com>
Reviewed-by: Honnappa Nagarahalli <honnappa.nagarahalli@arm.com>