ledtrig-blkdev: Add function placeholders needed by block changes

Add ledtrig_blkdev_disk_init() and ledtrig_blkdev_disk_cleanup()
placeholders.  (Implementations depend on block subsystem changes in
next commit.)

Signed-off-by: Ian Pilcher <arequipeno@gmail.com>

drivers/leds/trigger/ledtrig-blkdev-core.c

@@ -6,4 +6,15 @@
  *	Copyright 2021 Ian Pilcher <arequipeno@gmail.com>
  */
 
+#include <linux/leds.h>
+
 #include "ledtrig-blkdev.h"
+
+/**
+ * ledtrig_blkdev_disk_cleanup - remove a block device from the blkdev LED
+ * trigger
+ * @gd:	the disk to be removed
+ */
+void ledtrig_blkdev_disk_cleanup(struct gendisk *const gd)
+{
+}

include/linux/leds.h

@@ -10,6 +10,7 @@
 
 #include <dt-bindings/leds/common.h>
 #include <linux/device.h>
+#include <linux/genhd.h>
 #include <linux/kernfs.h>
 #include <linux/list.h>
 #include <linux/mutex.h>
@@ -605,4 +606,22 @@ static inline void ledtrig_audio_set(enum led_audio type,
 }
 #endif
 
+#if IS_ENABLED(CONFIG_LEDS_TRIGGER_BLKDEV)
+/**
+ * ledtrig_blkdev_disk_init - initialize the ledtrig field of a new gendisk
+ * @gd:	the gendisk to be initialized
+ */
+static inline void ledtrig_blkdev_disk_init(struct gendisk *const gd)
+{
+}
+void ledtrig_blkdev_disk_cleanup(struct gendisk *const gd);
+#else	/* CONFIG_LEDS_TRIGGER_BLKDEV */
+static inline void ledtrig_blkdev_disk_init(const struct gendisk *gd)
+{
+}
+static inline void ledtrig_blkdev_disk_cleanup(const struct gendisk *gd)
+{
+}
+#endif	/* CONFIG_LEDS_TRIGGER_BLKDEV */
+
 #endif		/* __LINUX_LEDS_H_INCLUDED */