P2P: Remove GO neg/invite special cases from search

P2P: Remove GO neg/invite special cases from search

There are separate states for these, so we can't really get into this
situation unless somebody tries to do multiple things at the same
time. p2p_connect stops find and CONNECT state is used to probe the peer
on its Listen channel with GO Negotiation Request frames. Similarly,
p2p_invite() stops find and INVITE state is used to probe the peer on
its Listen channel with Invitation Request frames. The older mechanism
of using Search state functionality to find the peer can be removed.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>