Use updated dl_type when checking actions that use fields

Update handling of the following actions to use the dl_type set by MPLS
push and pop actions if it differs from the original dl_type. This is
consistent with the existing checking of load actions and allows
their existing checks to enforce dl_type pre-requisites correctly.

	output_reg
	bundle
	reg_move
	stack_push
	stack_pop
	learn
	multipath

In order to avoid the verbosity of updating the flow for each applicable
action the update is treated as a common case and performed in
ofpact_check().  This was suggested by Jesse Gross.

Cc: Jesse Gross <jesse@nicira.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Jesse Gross <jesse@nicira.com>
OpenFlow-level flow-based tunneling support.

Adds tun_src and tun_dst match and set capabilities via new NXM fields
NXM_NX_TUN_IPV4_SRC and NXM_NX_TUN_IPV4_DST.  This allows management of
large number of tunnels via the flow tables, without requiring the tunnels
to be pre-configured.

Flow-based tunnels can be configured with options remote_ip=flow and
local_ip=flow.  local_ip=flow requires remote_ip=flow.  When set, the
tunnel remote IP address and/or local IP address is set from the flow,
instead of the tunnel configuration.

Example:

$ ovs-vsctl add-port br0 gre -- set Interface gre ofport_request=1 type=gre options:remote_ip=flow options:key=flow
$ ovs-ofctl add-flow br0 "in_port=LOCAL actions=set_tunnel:1,set_field:192.168.0.1->tun_dst,output:1"
$ ovs-ofctl add-flow br0 "in_port=1 tun_src=192.168.0.1 tun_id=1 actions=LOCAL"

Signed-off-by: Jarno Rajahalme <jarno.rajahalme@nsn.com>
Signed-off-by: Ben Pfaff <blp@nicira.com>
netdev: Factor restoring flags into new "struct netdev_saved_flags".

This gets rid of the only per-instance data in "struct netdev", which
will make it possible to merge "struct netdev_dev" into "struct netdev" in
a later commit.

Ed Maste wrote the netdev-bsd changes in this commit.

Signed-off-by: Ben Pfaff <blp@nicira.com>
Co-authored-by: Ed Maste <emaste@freebsd.org>
Signed-off-by: Ed Maste <emaste@freebsd.org>
Tested-by: Ed Maste <emaste@freebsd.org>