misc: Fix make distcheck

Add some missing header files
diff --git a/openbsc/include/openbsc/Makefile.am b/openbsc/include/openbsc/Makefile.am
index c1f3f13..8d454bb 100644
--- a/openbsc/include/openbsc/Makefile.am
+++ b/openbsc/include/openbsc/Makefile.am
@@ -3,4 +3,4 @@
 		 timer.h misdn.h chan_alloc.h telnet_interface.h paging.h \
 		 subchan_demux.h trau_frame.h e1_input.h trau_mux.h signal.h \
 		 gsm_utils.h ipaccess.h rs232.h openbscdefines.h rtp_proxy.h \
-		 bsc_rll.h
+		 bsc_rll.h mncc.h talloc.h transaction.h