resource-manager: Add syscommon_resman_get_resource_id()

resource-manager: Add syscommon_resman_get_resource_id()

 It is necessary that a plugin know about resource_id so that the plugin
invoke resource-manager functions that works on top of resource_id. To
this end, added getter for resource_id.
 - syscommon_resman_get_resource_id()
     The function gets resource_id of the given type. The id is resource
     instance created first.
 - syscommon_resman_get_number_of_instance()
     The function gets how may resource instances have been created
     on a specific resource type.

 To support these operations, the resource-manager internally manages
hashtable dedicated to reosurce_id. The hashtable maps resource_type
into head of resource_id list.

Change-Id: I9d0df9a098444af506a94a81d14fae0f20bc1e04
Signed-off-by: Youngjae Cho <y0.cho@samsung.com>