Default behaviour of accel-ppp when it receives DHCP request with same Option 82 but different MAC address
is termination of old session (with previous MAC address).
This option can turn off such behaviour, so multiple sessions with same Option 82 but different MAC may coesist.

Before this patch if agent-remote-id is not specified in config it get default value "accel-pppd".
Now if agent-remote-id is not specified then accel-ppp will not insert his Option 82 into relayed DHCP requests

ipoe: remove NETIF_F_HW_VLAN_CTAG_FILTER from virtual device features (fixed warn in register_netdevice) (v2)

Introducesed 2 new options:
[ipoe]
attr-dhcp-opt82-remote-id=
attr-dhcp-opt82-circuit-id=

Soft termination means that session won't be terminated immediately, but marked as terminated
and when client will request for lease renewal it will be NAKed and session will be terminated at this time.
By default soft termination is turned off, to enable it introduces new option 'soft-terminate=1'.
Also cli command 'terminate <session> hard' terminates session immediatly regardless of 'soft-terminate' option.

ipoe: remove NETIF_F_HW_VLAN_CTAG_FILTER from virtual device features (fixed warn in register_netdevice)

If password=csid then password will we same as Calling-Station-Id.

radius: override session's idle and timeout timers values by Idle-Timeout and Session-Timeout attributes

Signed-off-by: NFrançois Cachereul <f.cachereul@alphalink.fr>

This avaid allocating a ppp unit when authentication failed

Split establish_ppp in two functions estabish_ppp and
connect_ppp_channel. The fist one connect the channel on an instance of
/dev/ppp, allocate channel resources and start first ppp layer.
The second functions create ppp unit and connect the channel to this
unit. It is called after authentication.
destablish_ppp is also split in two function for symmetry and
ppp_terminate is adapted to handle the case when the unit is not
created.
Signed-off-by: NFrançois Cachereul <f.cachereul@alphalink.fr>

In the following patch PPP unit will be created after MRU negotation.
Signed-off-by: NFrançois Cachereul <f.cachereul@alphalink.fr>

This reverts commit c362f0d1.

* radius: major improvments
* radius: use NAS-Port-Id in Access-Accept for interface renaming
* radius: introduced "weight" and "backup" per-server options
* radius: introduced "attr-tunnel-type" option
* radius: introduced "max-fail" option
* ipoe: introduced "ip-unnumbered" option
* ipoe: improved vlan monitor
* ipoe: introduced "attr-dhcp-lease-time" option
* ipoe: send option 82 from DHCP request to radius
* ipoe: fixed passing packets in 'redirect on reject' mode
* ipoe: implemented handling relayed DHCP clients
* ipoe: implemented "L4 redirect on reject" for DHCP sessions
* ipoe: implemneted ability to send L4 redirect table/L4 redirect ipset via radius attributes
* pppoe: introduced "called-sid" option
* pppoe: improved AC-Cookie mechanism
* ippool: introduced "shuffle" option
* core: improved "single-session=replace" handling
* shaper: apply rate multiplier to integer values
* shaper: implemented fq_codel leaf qdisc
* shaper: fixed passing quantum parameter to kernel
* shaper: introduced "moderate-quantum" option
* shaper: introduced "fwmark" option
* ipv6: add support for prefixes greater than 64
* ppp: make LCP magic number negotiation not mandatory
* ppp: implement address/control and protocol field compression
* ppp: implemented delayed unit close via unit cache
* pppd_compat: pass IPV6_PREFIX and IPV6_DELEGATED_PREFIX to ip-up/ip-down scripts
* cli: introduced verbose option