ft: netdev: add return value to tx_associate

Prior to this, an error sending the FT Reassociation was treated
as fatal, which is correct for FT-over-Air but not for FT-over-DS.
If the actual l_genl_family_send call fails for FT-over-DS the
existing connection can be maintained and there is no need to
call netdev_connect_failed.

Adding a return to the tx_associate function works for both FT
types. In the FT-over-Air case this return will ultimately get
sent back up to auth_proto_rx_authenticate in which case will
call netdev_connect_failed. For FT-over-DS tx_associate is
actually called from the 'start' operation which can fail and
still maintain the existing connection.
3 files changed