netxen: fix license header

GNU General Public License is in file "COPYING".

Signed-off-by: Amit Kumar Salecha <amit.salecha@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/netxen/Makefile b/drivers/net/netxen/Makefile
index 11d94e2..861a059 100644
--- a/drivers/net/netxen/Makefile
+++ b/drivers/net/netxen/Makefile
@@ -18,7 +18,7 @@
 # MA  02111-1307, USA.
 # 
 # The full GNU General Public License is included in this distribution
-# in the file called LICENSE.
+# in the file called "COPYING".
 # 
 #