nios2: Set CONFIG_SYS_HZ to 1000 all nios2 boards.

   CONFIG_SYS_HZ was being calculated (incorrectly) in nios2 configuration
   headers. Updated comments to accurately describe timebase macros.

Signed-off-by: Scott McNutt <smcnutt@psyent.com>
diff --git a/include/configs/PK1C20.h b/include/configs/PK1C20.h
index 165dde0..874c20b 100644
--- a/include/configs/PK1C20.h
+++ b/include/configs/PK1C20.h
@@ -124,14 +124,16 @@
  * TIMEBASE --
  *
  * The high res timer defaults to 1 msec. Since it includes the period
- * registers, we can slow it down to 10 msec using TMRCNT. If the default
- * period is acceptable, TMRCNT can be left undefined.
+ * registers, the interrupt frequency can be reduced using TMRCNT.
+ * If the default period is acceptable, TMRCNT can be left undefined.
+ * TMRMS represents the desired mecs per tick (msecs per interrupt).
  *----------------------------------------------------------------------*/
+#define CONFIG_SYS_HZ			1000	/* Always 1000 */
 #define CONFIG_SYS_NIOS_TMRBASE	0x02120820	/* Tick timer base addr */
-#define CONFIG_SYS_NIOS_TMRIRQ		3		/* Timer IRQ num	*/
-#define CONFIG_SYS_NIOS_TMRMS		10		/* 10 msec per tick	*/
-#define CONFIG_SYS_NIOS_TMRCNT (CONFIG_SYS_NIOS_TMRMS * (CONFIG_SYS_CLK_FREQ/1000))
-#define CONFIG_SYS_HZ		(CONFIG_SYS_CLK_FREQ/(CONFIG_SYS_NIOS_TMRCNT + 1))
+#define CONFIG_SYS_NIOS_TMRIRQ		3	/* Timer IRQ num */
+#define CONFIG_SYS_NIOS_TMRMS		10	/* Desired period */
+#define CONFIG_SYS_NIOS_TMRCNT \
+		(CONFIG_SYS_NIOS_TMRMS * (CONFIG_SYS_CLK_FREQ/1000))
 
 /*------------------------------------------------------------------------
  * STATUS LED -- Provides a simple blinking led. For Nios2 each board