[PATCH] update legacy io handling for pmac

ppc can boot one single binary on prep, chrp and pmac boards.  ppc64 can
boot one single binary on pseries and G5 boards.  pmac has no legacy io,
probing for PC style legacy hardware (or accessing the legacy io area
regulary) may lead to a hard crash:

* add check for parport_pc, exit on pmac.  32bit chrp has no
  ->check_legacy_ioport, the probe is always called.  64bit chrp has
  check_legacy_ioport, check for a "parallel" node

* add check for isapnp, only PReP boards may have real ISA slots.  32bit
  PReP will have no ->check_legacy_ioport, the probe is always called.

* update code in i8042_platform_init.  Run ->check_legacy_ioport first,
  always call request_region.  No functional change.  Remove whitespace
  before i8042_reset init.

Signed-off-by: Olaf Hering <olaf@aepfle.de>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Adam Belay <ambx1@neo.rr.com>
Cc: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>