iflib: Use the framework run-state accessor in drivers

[kbowling]

Summary

Replace direct IFF_DRV_RUNNING reads in igbv, ixgbe, ixv, iavf, ixl,
ice, bnxt Ethernet, aq, enic and the axgbe PCI frontend with
iflib_is_running().  Keep each existing mailbox-ready, fault-state,
link-state and administrative-up condition: framework admission is not
a substitute for device-specific readiness.

This covers interrupt admission, operational link publication, VF
mailbox and VLAN replay, and live-configuration decisions.  Remove
ifnet temporaries used only to read the driver flags.

Replace the em and igc debug dumps' RUNNING/OACTIVE text with one
framework admission snapshot.  OACTIVE does not mean that the interface
or hardware is inactive.  Label the result as software admission rather
than link state or proof that DMA has stopped, and retain the queue
head/tail dumps and separate RS diagnostics.  Keep the filter register
and requested interface flags in the axgbe PCI promiscuous-mode trace,
but remove its unrelated legacy driver flags.

Use the parent Ethernet PF context for the bnxt RDMA running check,
retaining the link-state check and the existing IB_PORT_ACTIVE policy.
Both current RDMA construction paths use the PF netdev, and Ethernet
detach synchronously removes the RDMA auxiliary child before iflib frees
that context.  Declare the direct iflib module dependency.  This does
not transfer ownership of RDMA queues to iflib.

Leave the independent, non-iflib axgbe ARM frontend unchanged.