Add unit tests for libgtp gtpie.[ch] functions

This doesn't yet cover all the functions in gtpie.[ch], but testing half
of them is better than not testing any of them, so let's merge this
current state with a couple of TDOO's on what we still need to test.

Change-Id: I30a6dd8a01b7a074ef2d3936d186dfff6c79e6c0
diff --git a/tests/gtp/Makefile.am b/tests/gtp/Makefile.am
new file mode 100644
index 0000000..bb01e3d
--- /dev/null
+++ b/tests/gtp/Makefile.am
@@ -0,0 +1,19 @@
+AM_CFLAGS = -Wall -I$(top_srcdir)/include $(LIBOSMOCORE_CFLAGS) -g
+
+EXTRA_DIST = \
+	gtpie_test.ok \
+	$(NULL)
+
+noinst_PROGRAMS = \
+	gtpie_test \
+	$(NULL)
+
+gtpie_test_SOURCES = \
+	gtpie_test.c \
+	$(NULL)
+
+gtpie_test_LDADD = \
+	$(top_builddir)/lib/debug.o \
+	$(top_builddir)/gtp/libgtp.la \
+	$(LIBOSMOCORE_LIBS) \
+	$(NULL)