goodbye CIRCLEQ, welcome TAILQ
delete things that we don't need so we don't use them accidentally.
Provide the correct feature macros, so that we get to include our own
files not the compat copies.
Provide TAILQ_REPLACE for tmux, from FreeBSD.
Kill CIRCLEQ, nothing uses it and it will not work with gcc-4.8, so avoid
future accidents.
remove CIRCLEQ pages.
Bye CIRCLEQ
remove trailing whitespace.
Improve DEBUG message.
obsolete CIRCLEQ man pages
iwi_newstate should work along with ieee80211_new_state, not always
override it.
Include signal.h early for MiNT and Linux. From pkgsrc.
avoid NULL deref.
Avoid repainting after screen has been destroyed.
Reduce diffs with OpenBSD:
	- add functions we did not have
	- sort the same way
Mark fatal as dead.
Switch XC_HIGHPRI to run at IPL_SOFTSERIAL i.e. the highest software level.
Adjust pcu(9) to this xcall(9) change.  This may fix the problems after
x86 FPU was converted to use PCU, since it avoids heavy contention at the
lower levels (particularly, IPL_SOFTNET).  This is a good illustration why
software interrupts should generally avoid any blocking on locks.
Mention kmem_intr(9) routines.
Update xcall(9).
Fix previous, use the correct value for softint_establish (SOFTINT_SERIAL).