Add gsmtap utility functions to libosmocore
This is imported from OsmocomBB/Layer23
diff --git a/src/Makefile.am b/src/Makefile.am
index 1a7d87f..dc2309a 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -12,7 +12,7 @@
libosmocore_la_SOURCES = timer.c select.c signal.c msgb.c rxlev_stat.c \
tlv_parser.c bitvec.c comp128.c gsm_utils.c statistics.c \
write_queue.c utils.c rsl.c gsm48.c gsm48_ie.c \
- logging.c gsm0808.c rate_ctr.c
+ logging.c gsm0808.c rate_ctr.c gsmtap_util.c
if ENABLE_TALLOC
libosmocore_la_SOURCES += talloc.c