libcamera/base: Move event_notifier to base

Move the event notifier, and associated header updates.

Reviewed-by: Hirokazu Honda <hiroh@chromium.org>
Reviewed-by: Paul Elder <paul.elder@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>

src/libcamera/v4l2_videodevice.cpp

@@ -21,11 +21,11 @@
 
 #include <linux/version.h>
 
+#include <libcamera/base/event_notifier.h>
 #include <libcamera/base/log.h>
 
 #include <libcamera/file_descriptor.h>
 
-#include "libcamera/internal/event_notifier.h"
 #include "libcamera/internal/media_device.h"
 #include "libcamera/internal/media_object.h"