Pull up the following revisions, requested by msaitoh in ticket #1388:

sys/dev/pci/pcireg.h 1.147 via patch
sys/dev/pci/pci_subr.c 1.212, 1.215-1.217 via patch

- Change fast back-to-back "capable" to "enable" in pci_subr.c.
- Print Primary Discard Timer, Secondary Discard Timer, Discard
  Timer Status and Discard Timer SERR# Enable bit in pci_subr.c.
- Print some DPC register values not with %04x but with %08x because
  those are 32bit.
- Remove whitespace for consistency.
- Use macro.
- Whitespace fixes.

(martin)