Move adjtimedelta from kern_time.c to kern_tc.c.

This will simplify upcoming MP-safety diffs for the timecounting layer.

adjtimedelta is now accessed nowhere outside of kern_tc.c, so we can
remove its extern declaration from kernel.h.  Zeroing adjtimedelta
within timecounter_mtx before we jump the real-time clock is also a
bit safer than what we do now, as we are not racing a simultaneous
tc_windup() call from hardclock(), which itself can modify adjtimedelta
via ntp_update_second().

Discussed with visa@ and mpi@.

ok visa@

0 files changed, 0 insertions, 0 deletions