rt2x00: initialize last_reset

Initialize last_reset variable to INITIAL_JIFFIES, otherwise it is not
possible to test H/W reset for first 5 minutes of system run.

Fixes: e403fa31 ("rt2x00: add restart hw")
Reported-and-tested-by: Jonathan Liu <net147@gmail.com>
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

drivers/net/wireless/ralink/rt2x00/rt2x00debug.c

@@ -555,7 +555,7 @@ static ssize_t rt2x00debug_write_restart_hw(struct file *file,
 {
 	struct rt2x00debug_intf *intf =	file->private_data;
 	struct rt2x00_dev *rt2x00dev = intf->rt2x00dev;
-	static unsigned long last_reset;
+	static unsigned long last_reset = INITIAL_JIFFIES;
 
 	if (!rt2x00_has_cap_restart_hw(rt2x00dev))
 		return -EOPNOTSUPP;