nl80211: explicit userspace MPM

Secure mesh had the implicit requirement that the Mesh
Peering Management entity be in userspace.  However
userspace might want to implement an open MPM as well, so
specify a mesh setup parameter to indicate this.

Signed-off-by: Thomas Pedersen <thomas@cozybit.com>
cfg80211: rename mesh station types

The mesh station types used to refer to whether the
station was secure or nonsecure. Really the salient
information is whether it is managed by the kernel or
userspace

Signed-off-by: Thomas Pedersen <thomas@cozybit.com>
mac80211: support userspace MPM

Earlier mac80211 would check whether some kind of mesh
security was enabled, when the real question was "is the
MPM in userspace"?

Signed-off-by: Thomas Pedersen <thomas@cozybit.com>
nl80211: user_mpm overrides auto_open_plinks

If the user requested a userspace MPM, automatically
disable auto_open_plinks to fully disable the kernel MPM.

Signed-off-by: Thomas Pedersen <thomas@cozybit.com>
mac80211: disallow changing auto_open_plinks

while user MPM is running.

Signed-off-by: Thomas Pedersen <thomas@cozybit.com>
mac80211: init mesh timer for user authed STAs

There is a corner case which wasn't being covered:
userspace may authenticate and allocate stations,
but still leave the peering up to the kernel.

Initialize the peering timer if the MPM is not in
userspace, in a path which is taken when allocating
stations by both the kernel and userspace.

Signed-off-by: Thomas Pedersen <thomas@cozybit.com>