mac80211: Add econet patch for hwnat

Functionality is delivered by econet as a patch to backports. Functional content of this patch was not changed except aligning line number to new code base.

911-ECNT_hwnat_tx_hook_porting.patch Patch contains functionality for handling hw_nat packets and more debuging info from hw_nat. Patch is required to have hw_nat running.

Additional changes made in Makefile are necessary to apply 911-ECNT_hwnat_tx_hook_porting.patch only when target is econet (CONFIG_TARGET_iopsys_econet). All extra patches for econet placed in patches/econet/ directory will be applied after all patches from patches/subsys directory.

Signed-off-by: Marek Puzyniak marek.puzyniak@iopsys.eu

@AGnau @bartlomiej.grzeskowiak Please take a look. My change is in Makefile. What do you think about this way of adding vendor specific patches to backports. For other vendor builds this patch should not be applied. Concerning patch itself, is was delivered by econet to be applied to previous version of backports, so with the current version of backports some lines were shifted. I modified origin econet patch to apply on current version of backports without warnings.