parport->dev driver model support

Currently a parport_driver can't get a handle on the device node for the
underlying parport (PNPACPI, PCI, etc).  That prevents correct placement of
sysfs child nodes, which can affect things like power management.

This patch adds a field to "struct parport" pointing to that device node, and
updates non-legacy port drivers to initialize that device pointer.  That field
replaces the analagous PCI-only support in parport_pc.

[akpm@linux-foundation.org: fix powerpc build]
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>