gpt: Fix uuid string format

Change GPT UUID string format from UUID to GUID per specification.

Signed-off-by: Vincent Tinelli <vincent.tinelli@intel.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/cmd/gpt.c b/cmd/gpt.c
index 196f506..3e98821 100644
--- a/cmd/gpt.c
+++ b/cmd/gpt.c
@@ -54,7 +54,7 @@
 	if (e == NULL) {
 #ifdef CONFIG_RANDOM_UUID
 		debug("%s unset. ", str);
-		gen_rand_uuid_str(uuid_str, UUID_STR_FORMAT_STD);
+		gen_rand_uuid_str(uuid_str, UUID_STR_FORMAT_GUID);
 		setenv(s, uuid_str);
 
 		e = getenv(s);
diff --git a/disk/part_efi.c b/disk/part_efi.c
index 893cbbd..db0c890 100644
--- a/disk/part_efi.c
+++ b/disk/part_efi.c
@@ -463,7 +463,7 @@
 		str_uuid = partitions[i].uuid;
 		bin_uuid = gpt_e[i].unique_partition_guid.b;
 
-		if (uuid_str_to_bin(str_uuid, bin_uuid, UUID_STR_FORMAT_STD)) {
+		if (uuid_str_to_bin(str_uuid, bin_uuid, UUID_STR_FORMAT_GUID)) {
 			printf("Partition no. %d: invalid guid: %s\n",
 				i, str_uuid);
 			return -1;