Merge third_party/usrsctp/usrsctplib from https://chromium.googlesource.com/external/usrsctplib.git at a11b3c55b730332ac33e9a81d053aca3bf813b93

This commit was generated by merge_from_chromium.py.

Change-Id: I9db456b62724c4dd138eb2e19d4b6f670f1f34bb