datapath: Use nla_len() in queue_userspace_packet().

Commit e995e3df57ea4e27678bc0bea5eb30872994155b (Allow
OVS_USERSPACE_ATTR_USERDATA to be variable length.) introduced an
open coded version of nla_len() in queue_userspace_packet().  This
replaces it with the equivalent function call.

Signed-off-by: Jesse Gross <jesse@nicira.com>
datapath: Fix parsing invalid LLC/SNAP ethertypes

Before this patch, if an LLC/SNAP packet with OUI 00:00:00 had an ethertype
less than 1536 the flow key given to userspace in the upcall would contain the
invalid ethertype (for example, 3). If userspace attempted to insert a kernel
flow for this key it would be rejected by ovs_flow_from_nlattrs.

This patch allows OVS to pass the OFTest pktact.DirectBadLlcPackets.

Signed-off-by: Rich Lane <rlane@bigswitch.com>
Signed-off-by: Jesse Gross <jesse@nicira.com>
datapath: Remove CAPWAP tunneling support.

The CAPWAP implementation is just the encapsulation format and
therefore really not the full protocol.  While there were some
uses of it (primarily hardware support and UDP transport).  But
these are most likely better provided by VXLAN.

Following patch removes CAPWAP tunneling support.

Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Acked-by: Jesse Gross <jesse@nicira.com>