V4L/DVB: ir-core: Add callbacks for input/evdev open/close on IR core

Especially when IR needs to do polling, it generates lots of wakeups per
second. This makes no sense, if the input event device is closed.

Adds a callback handler to the IR hardware driver, to allow registering
an open/close ops.

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/include/media/ir-common.h b/include/media/ir-common.h
index 87f2ec7..e403a9a 100644
--- a/include/media/ir-common.h
+++ b/include/media/ir-common.h
@@ -50,6 +50,7 @@
 	struct ir_input_state   ir;
 	char                    name[32];
 	char                    phys[32];
+	int			users;
 
 	u32			running:1;
 	struct ir_dev_props	props;