ixgbe: implement SIOCGHWTSTAMP ioctl

This patch adds support for the new SIOCGHWTSTAMP ioctl, which enables a
process to determine the current timestamp configuration. In order to
implement this, store a copy of the timestamp configuration. In
addition, we can remove the 'int cmd' parameter as the new set_ts_config
function doesn't use it. I also fixed a typo in the function
description.

-v2
* Only save the settings after validating them

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
index 7280743..10b35d8 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
@@ -7197,7 +7197,9 @@
 
 	switch (cmd) {
 	case SIOCSHWTSTAMP:
-		return ixgbe_ptp_hwtstamp_ioctl(adapter, req, cmd);
+		return ixgbe_ptp_set_ts_config(adapter, req);
+	case SIOCGHWTSTAMP:
+		return ixgbe_ptp_get_ts_config(adapter, req);
 	default:
 		return mdio_mii_ioctl(&adapter->hw.phy.mdio, if_mii(req), cmd);
 	}