inotify: reimplement inotify using fsnotify

Reimplement inotify_user using fsnotify.  This should be feature for feature
exactly the same as the original inotify_user.  This does not make any changes
to the in kernel inotify feature used by audit.  Those patches (and the eventual
removal of in kernel inotify) will come after the new inotify_user proves to be
working correctly.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
diff --git a/init/Kconfig b/init/Kconfig
index d4e9671..5de1c17c 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -302,7 +302,8 @@
 
 config AUDIT_TREE
 	def_bool y
-	depends on AUDITSYSCALL && INOTIFY
+	depends on AUDITSYSCALL
+	select INOTIFY
 
 menu "RCU Subsystem"