tftpput: add save_addr and save_size global variables

We need something akin to load_addr to handle saving data.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/include/common.h b/include/common.h
index 9166ca1..825ab72 100644
--- a/include/common.h
+++ b/include/common.h
@@ -284,6 +284,8 @@
 int	source (ulong addr, const char *fit_uname);
 
 extern ulong load_addr;		/* Default Load Address */
+extern ulong save_addr;		/* Default Save Address */
+extern ulong save_size;		/* Default Save Size */
 
 /* common/cmd_doc.c */
 void	doc_probe(unsigned long physadr);