Merge nick-nhusb

- API / infrastructure changes to support memory management changes.
- Memory management improvements and bug fixes.
- HCDs should now be MP safe
- conversion to KERNHIST based debug
- FS/LS isoc support on ehci(4).
- conversion to kmem(9)
- Some USB 3 support - mostly from Takahiro HAYASHI (t-hash).
- interrupt transfers now get proper DMA operations
- general bug fixes
- kern/48308
- uhub status notification improvements
- umass(4) probe fix (applied to HEAD already)
- ohci(4) short transfer fix

Use IOCONF #define to determine component name.

Avoids having to manually retype info already in .ioconf.

Also, COMPONENT_SIMPLE -> RUMP_COMPONENT=simple. That way, we can add
other attributes where necessary. As "future directions", the "ioconf"
attribute for RUMP_COMPONENT can just be removed when a driver is
converted to modular and has a proper modcmd.

Make it easier to create rump kernel components, part 1.

Reduce copypasteware for the component constructors. If a constructor
calls only config_init_component(), handle it from a common source file
instead of copying the same(ish) file around to every component.

Add a COMMENT describing what each component roughly does.

"make describe" prints the comment.

Requested/inspired by Vincent Schwarzer on rumpkernel-users

continue consolidating non-modular option files

Rename usb_at_ugenhc.c to the more generic usb_at_hc.c now that
host controllers beyond ugenhc are attached.

branches: 1.6.14; 1.6.30; 1.6.32; 1.6.36;
enable this for amd64 too.

branches: 1.5.2; 1.5.4;
include usb_verbose in the component (at least for the time being)

branches: 1.4.2; 1.4.4; 1.4.6;
Use config pseudo-root keyword instead of monolithic configurations
starting from root.

Globally define -Wno-pointer-sign, as it has become a pointless
exercise of "add it to every Makefile individually".

XXX: should autosynchronize with the rest of the kernel buildflags
in sys/conf/Makefile.kern.inc.

I forgot I didn't fix kern/40505 yet, and hence using delay()/DELAY()
in rumps is hard due to some archs having a colorful idea of what
they should be like. So temporarily disable build of components
using those for non-i386 (use the no-need-to-mess-with-setlists
approach).

Move a bunch of rump components from dev/wip to dev/lib now that
they've reached a certain maturity.