drivers/net/*.c: Use static const

Using static const generally increases object text and decreases data size.
It also generally decreases overall object size.

Signed-off-by: Joe Perches <joe@perches.com>
diff --git a/drivers/net/eexpress.c b/drivers/net/eexpress.c
index 12c37d2..48ee51b 100644
--- a/drivers/net/eexpress.c
+++ b/drivers/net/eexpress.c
@@ -1103,7 +1103,7 @@
 		dev->dev_addr[i] = ((unsigned char *)hw_addr)[5-i];
 
 	{
-		static char irqmap[]={0, 9, 3, 4, 5, 10, 11, 0};
+		static const char irqmap[] = { 0, 9, 3, 4, 5, 10, 11, 0 };
 		unsigned short setupval = eexp_hw_readeeprom(ioaddr,0);
 
 		/* Use the IRQ from EEPROM if none was given */