dm: add uevent to core

This patch adds a uevent skeleton to device-mapper.

Signed-off-by: Mike Anderson <andmike@linux.vnet.ibm.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
diff --git a/drivers/md/Kconfig b/drivers/md/Kconfig
index a99af89..9b6fbf0 100644
--- a/drivers/md/Kconfig
+++ b/drivers/md/Kconfig
@@ -282,4 +282,10 @@
 
 	If unsure, say N.
 
+config DM_UEVENT
+	bool "DM uevents (EXPERIMENTAL)"
+	depends on BLK_DEV_DM && EXPERIMENTAL
+	---help---
+	Generate udev events for DM events.
+
 endif # MD