event: Add a command

Add a command to show the available events.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/MAINTAINERS b/MAINTAINERS
index 2786ada..6e5c022 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -812,6 +812,7 @@
 EVENTS
 M:	Simon Glass <sjg@chromium.org>
 S:	Maintained
+F:	cmd/event.c
 F:	common/event.c
 F:	include/event.h
 F:	test/common/event.c