rockchip: mkimage: play nice with dumpimage

Dumpimage (it invoked with "-T rkspi" or "-T rksd") would not work due
to check_params failing. These changes ensure that we can both be called
with an empty imagename.

Signed-off-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
Acked-by: Simon Glass <sjg@chromium.org>

tools/rkcommon.c

@@ -86,6 +86,9 @@ static struct spl_info *rkcommon_get_spl_info(char *imagename)
 {
 	int i;
 
+	if (!imagename)
+		return NULL;
+
 	for (i = 0; i < ARRAY_SIZE(spl_infos); i++)
 		if (!strncmp(imagename, spl_infos[i].imagename, 6))
 			return spl_infos + i;
@@ -98,17 +101,24 @@ int rkcommon_check_params(struct image_tool_params *params)
 	int i;
 
 	if (rkcommon_get_spl_info(params->imagename) != NULL)
-		return 0;
+		return EXIT_SUCCESS;
+
+	/*
+	 * If this is a operation (list or extract), the don't require
+	 * imagename to be set.
+	 */
+	if (params->lflag || params->iflag)
+		return EXIT_SUCCESS;
 
 	fprintf(stderr, "ERROR: imagename (%s) is not supported!\n",
-		strlen(params->imagename) > 0 ? params->imagename : "NULL");
+		params->imagename ? params->imagename : "NULL");
 
 	fprintf(stderr, "Available imagename:");
 	for (i = 0; i < ARRAY_SIZE(spl_infos); i++)
 		fprintf(stderr, "\t%s", spl_infos[i].imagename);
 	fprintf(stderr, "\n");
 
-	return -1;
+	return EXIT_FAILURE;
 }
 
 const char *rkcommon_get_spl_hdr(struct image_tool_params *params)