Add hb-ot-map-private.hh
diff --git a/src/Makefile.am b/src/Makefile.am
index 8e7ac47..dba3bb3 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -47,6 +47,7 @@
 	hb-ot-layout-gsubgpos-private.hh \
 	hb-ot-layout-gsub-private.hh \
 	hb-ot-layout-private.hh \
+	hb-ot-map-private.hh \
 	hb-ot-shape.cc \
 	hb-ot-shape-arabic.cc \
 	hb-ot-tag.c \