tweak jackd man page to reflect removal of -c c option

jackd/jackd.1.in

@@ -192,8 +192,10 @@ Unlock libraries GTK+, QT, FLTK, Wine.
 \fB\-v, \-\-verbose\fR
 Give verbose output.
 .TP
-\fB\-c, \-\-clocksource\fR (\fI c(ycle)\fR | \fI h(pet) \fR | \fI s(ystem) \fR)
-Select a specific wall clock (Cycle Counter, HPET timer, System timer).
+\fB\-c, \-\-clocksource\fR (\fI h(pet) \fR | \fI s(ystem) \fR)
+Select a specific wall clock (HPET timer or the system clock). Asking for
+the now removed cycle-counter timer usiung \fI-c c\fR will result in
+the use of the system clock.
 .TP
 \fB\-V, \-\-version\fR
 Print the current JACK version number and exit.