sky2: only bring up watchdog if link is active

This fixes the extra timer overhead that people were whining about
as a 2.6.23 regression.

Running the watchdog timer all the time is unneeded. Change it
to run only if link is up, and reduce frequency to save power.

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/net/sky2.h b/drivers/net/sky2.h
index dce4d27..72e12b7c 100644
--- a/drivers/net/sky2.h
+++ b/drivers/net/sky2.h
@@ -2045,12 +2045,13 @@
 	u8		     chip_rev;
 	u8		     pmd_type;
 	u8		     ports;
+	u8		     active;
 
 	struct sky2_status_le *st_le;
 	u32		     st_idx;
 	dma_addr_t   	     st_dma;
 
-	struct timer_list    idle_timer;
+	struct timer_list    watchdog_timer;
 	struct work_struct   restart_work;
 	int		     msi;
 	wait_queue_head_t    msi_wait;