sandbox: Boot in U-Boot through the standard call

Most architectures use jump_to_image_no_args() to jump from SPL to U-Boot.
At present sandbox is special in that it jumps in its
spl_board_load_image() call. This is not strictly correct, and means that
sandbox misses out some parts of board_init_r(), just as calling
bloblist_finish(), for example.

Change spl_board_load_image() to just identify the filename to boot, and
implement jump_to_image_no_args() to actually jump to it.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/sandbox/cpu/os.c b/arch/sandbox/cpu/os.c
index 7b59e04..aa92694 100644
--- a/arch/sandbox/cpu/os.c
+++ b/arch/sandbox/cpu/os.c
@@ -666,8 +666,11 @@
 
 	err = execv(fname, argv);
 	os_free(argv);
-	if (err)
+	if (err) {
+		perror("Unable to run image");
+		printf("Image filename '%s'\n", mem_fname);
 		return err;
+	}
 
 	return unlink(fname);
 }
@@ -747,17 +750,7 @@
 
 int os_spl_to_uboot(const char *fname)
 {
-	struct sandbox_state *state = state_get_current();
-	char *argv[state->argc + 1];
-	int ret;
-
-	memcpy(argv, state->argv, sizeof(char *) * (state->argc + 1));
-	argv[0] = (char *)fname;
-	ret = execv(fname, argv);
-	if (ret)
-		return ret;
-
-	return unlink(fname);
+	return os_jump_to_file(fname);
 }
 
 void os_localtime(struct rtc_time *rt)