tests: Split SCTP tests to its own file and run them conditionally

Some systmes (like the ones available in OBS) don't support creating
SCTP sockets, so we need to skip those tests there.

Change-Id: I1d16280674625877ec22cc60cbc5deb67868a656
diff --git a/configure.ac b/configure.ac
index fbdcb57..b07a3bd 100644
--- a/configure.ac
+++ b/configure.ac
@@ -197,6 +197,10 @@
 	LIBS=$old_LIBS
 ])
 
+AC_ARG_ENABLE([sctp-tests], [AS_HELP_STRING([--disable-sctp-tests], [Do not run socket tests requiring system SCTP support])],
+	[ENABLE_SCTP_TESTS=$enableval], [ENABLE_SCTP_TESTS="yes"])
+AM_CONDITIONAL(ENABLE_SCTP_TESTS, test x"$ENABLE_SCTP_TESTS" = x"yes")
+
 AC_ARG_ENABLE(plugin,
 	[AS_HELP_STRING(
 		[--disable-plugin],