Move atomic ops into their own header
diff --git a/src/Makefile.am b/src/Makefile.am
index 63d4e31..fc4cb29 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -15,6 +15,7 @@
 HBCFLAGS =
 HBLIBS =
 HBSOURCES =  \
+	hb-atomic-private.hh \
 	hb-blob.cc \
 	hb-buffer-private.hh \
 	hb-buffer.cc \