nat: Extract the message re-writing from the utils to a dedicated file
Move the code around to make it more clear what the routines should do.
diff --git a/openbsc/src/osmo-bsc_nat/Makefile.am b/openbsc/src/osmo-bsc_nat/Makefile.am
index d5b06da..8d9f732 100644
--- a/openbsc/src/osmo-bsc_nat/Makefile.am
+++ b/openbsc/src/osmo-bsc_nat/Makefile.am
@@ -6,7 +6,7 @@
osmo_bsc_nat_SOURCES = bsc_filter.c bsc_mgcp_utils.c bsc_nat.c bsc_nat_utils.c \
- bsc_nat_vty.c bsc_sccp.c bsc_ussd.c bsc_nat_ctrl.c
+ bsc_nat_vty.c bsc_sccp.c bsc_ussd.c bsc_nat_ctrl.c bsc_nat_rewrite.c
osmo_bsc_nat_LDADD = $(top_builddir)/src/libcommon/libcommon.a \
$(top_builddir)/src/libmgcp/libmgcp.a \
$(top_builddir)/src/libbsc/libbsc.a \