Revert r260440.  I didn't realize that most of this change was already
in effect due to r250753.  That is sufficient for all SoCs with a 32 byte
cache line size.  Systems with 64 byte cache lines will need the option;
that will be done in a separate commit.

Thanks to loos@ for pointing out r250753.
Add option USB_HOST_ALIGN=64 for all SoCs that have 64 byte cache lines.
Revert r234666.  Clearing TWSI IRQ seems to cause watchdog timeout
on old Yukon II controllers.

Tested by:	bsam
MFC after:	2 weeks
Spacing.
Unlock entry before retry.

Submitted by:	melifaro
MFC after:	1 week
In IPv6 code examples, use the correct v6 socket.

MFC after:	1 week
Implement vd_drawrect and vd_setpixel for vt(9)'s VGA driver.

Sponsored by:	The FreeBSD Foundation
Fix the build with DEBUG enabled.  Where possible, fix style(9) issues.

Reviewed by:	bde
Approved by:	adrian (mentor)