overlay: Add graph for GPU power consumption

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
diff --git a/overlay/Makefile.am b/overlay/Makefile.am
index cc748a7..516508b 100644
--- a/overlay/Makefile.am
+++ b/overlay/Makefile.am
@@ -25,6 +25,8 @@
 	gpu-freq.c \
 	igfx.h \
 	igfx.c \
+	power.h \
+	power.c \
 	rc6.h \
 	rc6.c \
 	$(NULL)