New config option vif_pool_mapping is added and pools_vif_drivers is
deprecated. The newer vif_pool_mapping is simply inverted mapping of
pools_vif_drivers.
Also, with the scoping ability added in cb2d308f84, independent
drv_pool instances can be acquired from base driver manager.
Earlier as a single instance of drv_pool was used by all
pod_drivers. This meant only the pod_driver which was
passed to drv_pool.set_vif_driver finally was used (for a given
drv_pool).
Please see release notes for further details.
Related-Bug: 1747406
Change-Id: Id0137f6b1a78e7aa3e3d3de639a5e989f4fd408c
Signed-off-by: Yash Gupta <y.gupta@samsung.com>