net: Make net_transfer() a static function

This should be a static function so it can be inlined.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Mike Frysinger <vapier@gentoo.org>

net/tftp.c

@@ -198,7 +198,7 @@ store_block(unsigned block, uchar *src, unsigned len)
 }
 
 /* Clear our state ready for a new transfer */
-void new_transfer(void)
+static void new_transfer(void)
 {
 	TftpLastBlock = 0;
 	TftpBlockWrap = 0;