Remove the remaining uses of err(3)

[haesbaert]

There are some panic calls that maybe we can remove, unwrap the stack and kill the queue, better than killing the program, these are basically extra bug checking so they would only trigger if we screwed up. Still, this is a library, and libraries shouldn't exit.

btf.c:          err(1, "bit offset not multiple of 8");
quark.c:                err(1, "clock_gettime");
quark.c:                err(1, "we got consecutive collisions, this is a bug");
quark.c:                err(1, "collision on pidtime tree, this is a bug");
kprobe_queue.c:         errx(1, "getting an event larger than wrapped buf");