ixgbe: Fix Receive Address Register (RAR) cleaning and accounting

This fixes an issue when clearing out the RAR entries.  If RAR[0]
is the only address in use, don't clear the others.
Signed-off-by: NShannon Nelson <shannon.nelson@intel.com>
Signed-off-by: NPeter P Waskiewicz Jr <peter.p.waskiewicz.jr@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ixgbe/ixgbe_common.c

@@ -1382,10 +1382,10 @@ s32 ixgbe_update_uc_addr_list_generic(struct ixgbe_hw *hw,
 	hw->addr_ctrl.overflow_promisc = 0;
 
 	/* Zero out the other receive addresses */
-	hw_dbg(hw, "Clearing RAR[1-%d]\n", uc_addr_in_use);
-	for (i = 1; i <= uc_addr_in_use; i++) {
-		IXGBE_WRITE_REG(hw, IXGBE_RAL(i), 0);
-		IXGBE_WRITE_REG(hw, IXGBE_RAH(i), 0);
+	hw_dbg(hw, "Clearing RAR[1-%d]\n", uc_addr_in_use + 1);
+	for (i = 0; i < uc_addr_in_use; i++) {
+		IXGBE_WRITE_REG(hw, IXGBE_RAL(1+i), 0);
+		IXGBE_WRITE_REG(hw, IXGBE_RAH(1+i), 0);
 	}
 
 	/* Add the new addresses */