This calls the existing errno translation helpers from the callbacks,
adding trivial wrappers where necessary. For cmds that have no
sophisticated errno translation, default to -EIO.

For IPA cmds with no callback, fall back to a minimal default. This is
currently being used by qeth_l3_send_setrouting().

Thus having all converted all callbacks, remove the legacy path in
qeth_send_control_data_cb().
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>