Revision 318778

MFC r318399:
  Set M_BCAST and M_MCAST flags on mbuf sent via divert socket.

  r290383 has changed how mbufs sent by divert socket are handled.
  Previously they are always handled by slow path processing in ip_input().
  Now ip_tryforward() is invoked from ip_input() before in_broadcast() check.
  Since diverted packet lost all mbuf flags, it passes the broadcast check
  in ip_tryforward() due to missing M_BCAST flag. In the result the broadcast
  packet is forwarded to the wire instead of be consumed by network stack.

  Add in_broadcast() check to the div_output() function. And restore the
  M_BCAST flag if destination address is broadcast for the given network
  interface.

  PR:		209491