drivers/net/rtl8169.c: Fix GCC 4.6 build warning

Fix:
rtl8169.c: In function 'rtl_init':
rtl8169.c:742:13: warning: variable 'printed_version' set but not used
[-Wunused-but-set-variable]

Signed-off-by: Wolfgang Denk <wd@denx.de>
diff --git a/drivers/net/rtl8169.c b/drivers/net/rtl8169.c
index b81dcad..1ad13bd 100644
--- a/drivers/net/rtl8169.c
+++ b/drivers/net/rtl8169.c
@@ -739,7 +739,6 @@
 static int rtl_init(struct eth_device *dev, bd_t *bis)
 {
 	static int board_idx = -1;
-	static int printed_version = 0;
 	int i, rc;
 	int option = -1, Cap10_100 = 0, Cap1000 = 0;
 
@@ -751,8 +750,6 @@
 
 	board_idx++;
 
-	printed_version = 1;
-
 	/* point to private storage */
 	tpc = &tpx;