Add UPower Device interface

Add a YAML description of the UPower Device interface defined at
https://upower.freedesktop.org/docs/Device.html

Signed-off-by: Shawn McCarney <shawnmm@us.ibm.com>
Change-Id: Ib70d6525b913cf06da4e93a53e332487126f1db0
diff --git a/gen/org/meson.build b/gen/org/meson.build
index 6488f22..dc6fcbb 100644
--- a/gen/org/meson.build
+++ b/gen/org/meson.build
@@ -1,2 +1,3 @@
 # Generated file; do not modify.
+subdir('freedesktop')
 subdir('open_power')