block: genhd: Add partition name to the partition info uevent callback

For disk and partition devices, add new uevent parameter:
PARTNAME specifices the partition name of a partition device

Signed-off-by: Dima Zavin <dima@android.com>

fs/partitions/check.c

@@ -371,6 +371,8 @@ static int part_uevent(struct device *dev, struct kobj_uevent_env *env)
 	struct hd_struct *part = dev_to_part(dev);
 
 	add_uevent_var(env, "PARTN=%u", part->partno);
+	if (part->info && part->info->volname[0])
+		add_uevent_var(env, "PARTNAME=%s", part->info->volname);
 	return 0;
 }