[netdrvr de2104x] store PCI bus addresses in unsigned long

BZ# 4475.
diff --git a/drivers/net/tulip/de2104x.c b/drivers/net/tulip/de2104x.c
index fc353e3..a22d001 100644
--- a/drivers/net/tulip/de2104x.c
+++ b/drivers/net/tulip/de2104x.c
@@ -1934,7 +1934,7 @@
 	struct de_private *de;
 	int rc;
 	void __iomem *regs;
-	long pciaddr;
+	unsigned long pciaddr;
 	static int board_idx = -1;
 
 	board_idx++;