Move seq_compare into its own header file

include/tins/internals.h

@@ -30,26 +30,11 @@
 #ifndef TINS_INTERNALS_H
 #define TINS_INTERNALS_H
 
-#include <stdint.h>
 #include "detail/type_traits.h"
 #include "detail/address_helpers.h"
 #include "detail/icmp_extension_helpers.h"
 #include "detail/smart_ptr.h"
 #include "detail/pdu_helpers.h"
-
-/**
- * \cond
- */
-namespace Tins {
-namespace Internals {
-
-// Compares sequence numbers as defined by RFC 1982.
-int seq_compare(uint32_t seq1, uint32_t seq2);
-
-} // namespace Internals
-} // namespace Tins
-/**
- * \endcond
- */
+#include "detail/sequence_number_helpers.h"
 
 #endif