fit_check_sign: Allow selecting the configuration to verify

This tool always verifies the default configuration. It is useful to be
able to verify a specific one. Add a command-line flag for this and plumb
the logic through.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/tools/image-host.c b/tools/image-host.c
index b3ec197..dfea48e 100644
--- a/tools/image-host.c
+++ b/tools/image-host.c
@@ -1025,12 +1025,13 @@
 }
 
 #ifdef CONFIG_FIT_SIGNATURE
-int fit_check_sign(const void *fit, const void *key)
+int fit_check_sign(const void *fit, const void *key,
+		   const char *fit_uname_config)
 {
 	int cfg_noffset;
 	int ret;
 
-	cfg_noffset = fit_conf_get_node(fit, NULL);
+	cfg_noffset = fit_conf_get_node(fit, fit_uname_config);
 	if (!cfg_noffset)
 		return -1;
 
@@ -1039,6 +1040,7 @@
 	ret = fit_config_verify(fit, cfg_noffset);
 	if (ret)
 		return ret;
+	printf("Verified OK, loading images\n");
 	ret = bootm_host_load_images(fit, cfg_noffset);
 
 	return ret;