ttydisc_rint_simple() expects to be called with the tty lock held.
Use debug.dtrace.providers when verifying a "depends_on provider" pragma.

This allows such pragmas to be used when dtrace isn't running as root
(e.g. with dtrace -h). Also revert my earlier change to io.d - this
change is the "real" fix.
Revert my earlier locking change to syscons(4), it was incorrect.
Make sure we don't send SYNCHRONIZE_CACHE commands to certain iPods.
Add the NO_SYNC_CACHE quirk to all Apple USB MSC devices and revert my
last commit in this area.
Use a variable for the "full" binary or shared library.

Fix breakage of the beforelinking target.
Make sure that beforelinking explicitly depends on the object files.
Add r219888, the original import of vt(4) into ed@'s newcons branch.
Import r219889 (update terminus font version).
Import r219897 (accomodate upstream KPI changes).
Fix some warnings emitted by clang.
Add a kernel config which uses vt(4) instead of syscons(4).