add BSSLAP coding for Location Services

BSSLAP: there are APDUs transferred in BSSMAP-LE Connection Oriented
Information messages on Lb between BSC and SMLC.
Add BSSLAP coding for these APDU messages:
- TA Layer3
- TA Request
- TA Response, possibly containing Location Estimate coded in GAD
- Reject
- Reset (for intra-BSS handover during TA Request)
- Abort (for inter-BSS handover)

Add encoding and decoding tests.

Change-Id: I6409c4bcac402dc7626a3afce9081c59cd715fe8
diff --git a/tests/Makefile.am b/tests/Makefile.am
index c4e6b9f..fc99485 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -39,6 +39,7 @@
                  i460_mux/i460_mux_test					\
 		 bitgen/bitgen_test					\
 		 gad/gad_test						\
+		 bsslap/bsslap_test					\
 		 $(NULL)
 
 if ENABLE_MSGFILE
@@ -285,6 +286,9 @@
 gad_gad_test_SOURCES = gad/gad_test.c
 gad_gad_test_LDADD = $(LDADD) $(top_builddir)/src/gsm/gad.o
 
+bsslap_bsslap_test_SOURCES = bsslap/bsslap_test.c
+bsslap_bsslap_test_LDADD = $(LDADD) $(top_builddir)/src/gsm/libosmogsm.la
+
 # The `:;' works around a Bash 3.2 bug when the output is not writeable.
 $(srcdir)/package.m4: $(top_srcdir)/configure.ac
 	:;{ \
@@ -366,6 +370,7 @@
 	     i460_mux/i460_mux_test.ok \
 	     bitgen/bitgen_test.ok \
 	     gad/gad_test.ok \
+	     bsslap/bsslap_test.ok \
 	     $(NULL)
 
 if ENABLE_LIBSCTP