Log Message:
sysutils/whowatch: Fix LP64 and DragonFly regression

1) The 4th argument of the sysctl function requires type size_t, not int,
   which matters for LP64.
2) DragonFly's kinfo structure changed dramatically a few years ago,
   breaking this package.  Repatched.
3) sysctl can return pid of -1 for pure kernel processes which must be
   skipped to avoid a segfault.