MFC r260486:
Remove very low default limit of 4 nfsd threads.  nfsd's own default is
8 * hw.ncpu, that sounds more appropriate for these SMP/NCQ/... days.
MFC r261899:

Similar to r260026, disable warning about unused functions for
ieee80211_adhoc.c, ieee80211_hostap.c and ieee80211_sta.c.