m68knommu: fix ColdFire definition of CLOCK_TICK_RATE

The good definition of CLOCK_TICK_RATE for coldfires has been lost in the
merge of m68k and m68knommu include files.  Restore it.  Culprit :
commit ebafc17

Signed-off-by: Philippe De Muyter <phdm@macqel.be>
Signed-off-by: Greg Ungerer <gerg@uclinux.org>

arch/m68k/include/asm/timex.h

@@ -3,10 +3,23 @@
  *
  * m68k architecture timex specifications
  */
-#ifndef _ASMm68k_TIMEX_H
-#define _ASMm68k_TIMEX_H
+#ifndef _ASMm68K_TIMEX_H
+#define _ASMm68K_TIMEX_H
 
+#ifdef CONFIG_COLDFIRE
+/*
+ * CLOCK_TICK_RATE should give the underlying frequency of the tick timer
+ * to make ntp work best.  For Coldfires, that's the main clock.
+ */
+#include <asm/coldfire.h>
+#define CLOCK_TICK_RATE	MCF_CLK
+#else
+/*
+ * This default CLOCK_TICK_RATE is probably wrong for many 68k boards
+ * Users of those boards will need to check and modify accordingly
+ */
 #define CLOCK_TICK_RATE	1193180 /* Underlying HZ */
+#endif
 
 typedef unsigned long cycles_t;