net: move bootfile init into eth_initialize

All arches init this the same way, so move the logic into the core
net code to avoid duplicating it everywhere else.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Reviewed-by: Joe Hershberger <joe.hershberger@ni.com>
diff --git a/arch/sh/lib/board.c b/arch/sh/lib/board.c
index d71cca4..34d7881 100644
--- a/arch/sh/lib/board.c
+++ b/arch/sh/lib/board.c
@@ -190,15 +190,8 @@
 	bb_miiphy_init();
 #endif
 #if defined(CONFIG_CMD_NET)
-	{
-		char *s;
-		puts("Net:   ");
-		eth_initialize(gd->bd);
-
-		s = getenv("bootfile");
-		if (s != NULL)
-			copy_filename(BootFile, s, sizeof(BootFile));
-	}
+	puts("Net:   ");
+	eth_initialize(gd->bd);
 #endif /* CONFIG_CMD_NET */
 
 	while (1) {