filter: Move the method definition to the filter module
Move the filter methods to the filter module. This is
still only usable for the NAT and the _dt/_cr filter
routines need to move back to the bsc_nat in the long
run.
diff --git a/openbsc/src/osmo-bsc_nat/bsc_nat.c b/openbsc/src/osmo-bsc_nat/bsc_nat.c
index 5c3b696..ebd291b 100644
--- a/openbsc/src/osmo-bsc_nat/bsc_nat.c
+++ b/openbsc/src/osmo-bsc_nat/bsc_nat.c
@@ -39,6 +39,7 @@
#include <openbsc/bsc_msc.h>
#include <openbsc/bsc_nat.h>
#include <openbsc/bsc_nat_sccp.h>
+#include <openbsc/bsc_msg_filter.h>
#include <openbsc/ipaccess.h>
#include <openbsc/abis_nm.h>
#include <openbsc/socket.h>