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/bootm.c b/cmd/bootm.c
index 62ee7c4..931d53f 100644
--- a/cmd/bootm.c
+++ b/cmd/bootm.c
@@ -144,7 +144,8 @@
 		char *local_args[2];
 		local_args[0] = (char *)cmd;
 		local_args[1] = NULL;
-		printf("Automatic boot of image at addr 0x%08lX ...\n", load_addr);
+		printf("Automatic boot of image at addr 0x%08lX ...\n",
+		       image_load_addr);
 		return do_bootm(cmdtp, 0, 1, local_args);
 	}
 
@@ -232,7 +233,7 @@
 	int	rcode = 0;
 
 	if (argc < 2) {
-		return image_info(load_addr);
+		return image_info(image_load_addr);
 	}
 
 	for (arg = 1; arg < argc; ++arg) {