Remove a really noisy printf left over from debugging hardware errata.
Two small fixes:
  Set promiscuous code was unconditionally turning off multicast when
  turning off promiscuous mode, this should only be done when there are
  less than MAX groups. Thanks to Mike Karels for this correction.

  Second, the overtmp interrupt setup/detection was wrong, correcting it.

MFC after:	one week
Fix a typo: the RXD0 pin is PA18, not PA19.
Redo the workaround for at91rm9200 erratum #26 in a way that doesn't
cause a lockup on some rm92 hardware.
Change defines in the igb driver to allow an easier selection of
the older if_start/non-multiqueue interface from the stack. This
is not the default, but can be turned on in the Makefile now regardless
of the OS level to allow either testing or use of ALTQ.

MFC after: one week