[ospfd] Raise ExchangeDone earlier, avoid often needless round of DD packets

[ospfd] Raise ExchangeDone earlier, avoid often needless round of DD packets

2006-08-03 Paul Jakma <paul.jakma@sun.com>

	* ospf_packet.c: (ospf_make_db_desc) Unset the DD More bit
	  after constructing the packet, if appropriate.
	  (ospf_db_desc_proc) Speed up Exchange, slave should raise
	  ExchangeDone earlier, as RFC mandates, by forming its reply
	  before deciding whether both sides are done, avoids a
	  needless round of empty DD packet exchanges at the end of
	  Exchange, hence speeding up ExchangeDone.
	  (ospf_db_desc) use UNSET_FLAG macro.