Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Implement /dev/cardbus%d.cis, same thing as /dev/pccard%d.cis. There
are some rough edges with this still, but it seems to work well enough
to commit.

I don't think that these modules should export symbols at all. All
intermodule communication is done via kobj calls. If anything
currently depends on them, let it break so that we can fix it. Maybe
we'll need to export some of the card_if.c or power_if.c symbols, but
I think those should be in the base kernel (since all *_if.c should be
in the base kernel for just these reasons).

Drop <bsd.man.mk> support from <bsd.kmod.mk>.

Not objected to by: -current

Turn on unconditional symbol export for modules whose API is
not clear enough, will require additional analysis, or will
require some input from their maintainers.

Use a consistent style and one much closer to the rest of /usr/src

A bunch of newcard/cardbus changes that's been sitting in my tree for a while:

- Make pccbb/cardbus kld loadable and unloadable.
- Make pccbb/cardbus use the power interface from pccard instead of inventing its own.
- some other minor fixes

Use .include <bsd.kmod.mk> to get to ../../*/conf/kmod.mk instead of
encoding the relative path.

Pull in sys/conf/kmod.mk, rather than /usr/share/mk/bsd.kmod.mk.
This means that the kernel can be totally self contained now and is not
dependent on the last buildworld to update /usr/share/mk. This might
also make it easier to build 5.x kernels on 4.0 boxes etc, assuming
gensetdefs and config(8) are updated.

Removed special rules for building and cleaning device interface files
and empty options files. The rules are now generated automatically in
bsd.kmod.mk. Cleaned up related things ($S and ${CLEANFILES}).

Module name is cardbus, not pccard.

Add modules for cardbus and the cardbus bridge driver. Files needed
to build these to be committed next.

Again, not added to sys/modules/Makefile