wifi: iwlwifi: mvm: fix P2P-Device binding handling

In the Linux kernel, the following vulnerability has been resolved:

wifi: iwlwifi: mvm: fix P2P-Device binding handling

Our binding handling for P2P-Device can run into the following
scenario, as observed by our testing:

- a station interface is connected on some channel
- the P2P-Device does a remain-on-channel (ROC) on that channel
- the ROC ends, and the P2P-Device is removed from the binding,
but the phy_ctxt pointer is left around as a PHY cache so we
don't need to recalibrate to the channel again and again in
case it's not shared
- a binding update by the station interface, even a removal,
will re-add the P2P-Device to the binding
- the P2P-Device is removed, which removes the PHY context, but
it's still in the binding so the firmware crashes

Since the P2P device is removed from the binding and only re-
added by unrelated code, but we want to keep the phy_ctxt around
as a cache for future ROC usage, fix it by adding a boolean that
indicates whether or not the P2P-Device should be added to the
binding, and handle that in the binding iterator. That way, the
station interface cannot re-add the P2P-Device to the binding
when that isn't active.