* sigproc.h: Make some functions regparm.

* sigproc.h: Make some functions regparm.
* sigproc.cc (checkstate): Make regparm.
(getevent): Change parameters in declaration, rename from getsem, make regparm.
(sig_send): Recognize that nosync is now an event.  Remove some old cruft from
previous interrupt anywhere signal handler.
(getevent): Change parameters in definition, rename from getsem.  Allocate
event rather than semaphore.
(wait_sig): Treat sigcatch_nosync as an event.