Address some signed/unsigned warnings reported by Thomas Zimmermann in https://bugzilla.mozilla.org/show_bug.cgi?id=970271
Address some signed/unsigned warnings reported by
Thomas Zimmermann in
https://bugzilla.mozilla.org/show_bug.cgi?id=970271

sctplab/sctp-refimpl,xwhuang/sctp-refimpl,sctplab/sctp-refimpl,deepak899/sctp-refimpl,xwhuang/sctp-refimpl,deepak899/sctp-refimpl,sctplab/sctp-refimpl,xwhuang/sctp-refimpl,deepak899/sctp-refimpl,sctplab/sctp-refimpl,sctplab/sctp-refimpl,deepak899/sctp-refimpl,xwhuang/sctp-refimpl,sctplab/sctp-refimpl,deepak899/sctp-refimpl,xwhuang/sctp-refimpl,deepak899/sctp-refimpl,xwhuang/sctp-refimpl