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

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

Convert isp(4) and ispfw(4) to use firmware(9) to manage firmware
loading for the QLogic cards.

Because isp(4) exists before the root is mounted, it's not really
possible for us to use the kernel's linker to load modules directly
from disk- that's really too bad.

However, the this is still a net win in in that the firmware has
been split up on a per chip (and in some cases, functionality)
basis, so the amount of stuff loaded *can* be substantially less
than the 1.5MB of firmware images that ispfw now manages. That is,
each specific f/w set is now also built as a module. For example,
QLogic 2322 f/w is built as isp_2322.ko and Initiator/Target 1080
firmware is built as isp_1080_it.ko.

For compatibility purposes (i.e., to perturb folks the least), we
also still build all of the firmware as one ispfw.ko module.

This allows us to let 'ispfw_LOAD' keep on working in existing
loader.conf files. If you now want to strip this down to just
the firmware for your h/w, you can then change loader.conf to
load the f/w you specifically want.

We also still allow for ispfw to be statically built (e.g., for
PAE and sparc64).

Future changes will look at f/w unloading and also role switching
that then uses the kernel linker to load different ips f/w sets.
MFC after: 2 months