Don't check for CPU scaling anymore

Without cycle counting, CPU scaling isn't necessarily bad anymore, so we
don't have to worry the user.

The purpose of this commit is to get rid of JACK_TIMER_CYCLE_COUNTER.

jackd/jackd.c

@@ -919,7 +919,7 @@ main (int argc, char *argv[])
 
 	copyright (stdout);
 
-	if (do_sanity_checks && (0 < sanitycheck (realtime, (clock_source == JACK_TIMER_CYCLE_COUNTER)))) {
+	if (do_sanity_checks && (0 < sanitycheck (realtime, FALSE))) {
 		return -1;
 	}