image: Rename load_addr, save_addr, save_size

These global variables are quite short and generic. In fact the same name
is more often used locally for struct members and function arguments.

Add a image_ prefix to make them easier to distinguish.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/cmd/bmp.c b/cmd/bmp.c
index d2a39f6..1e4c972 100644
--- a/cmd/bmp.c
+++ b/cmd/bmp.c
@@ -95,8 +95,8 @@
 	ulong addr;
 
 	switch (argc) {
-	case 1:		/* use load_addr as default address */
-		addr = load_addr;
+	case 1:		/* use image_load_addr as default address */
+		addr = image_load_addr;
 		break;
 	case 2:		/* use argument */
 		addr = simple_strtoul(argv[1], NULL, 16);
@@ -116,8 +116,8 @@
 	splash_get_pos(&x, &y);
 
 	switch (argc) {
-	case 1:		/* use load_addr as default address */
-		addr = load_addr;
+	case 1:		/* use image_load_addr as default address */
+		addr = image_load_addr;
 		break;
 	case 2:		/* use argument */
 		addr = simple_strtoul(argv[1], NULL, 16);