Replace bind2nd with lambdas in turnport.cc for C++ 17 compatibility.
Replace bind2nd with lambdas in turnport.cc for C++ 17 compatibility.

Bug: webrtc:8779
Change-Id: I0416cd6dff60b840734fb4e236a48ddcd84ef817
Reviewed-on: https://webrtc-review.googlesource.com/40981
Commit-Queue: Qingsi Wang <1c4f50fe02fab79f81be17f4e2f574c199f33efd@google.com>
Reviewed-by: Taylor Brandstetter <f49cf6381e322b147053b74e4500af8533ac1e4c@webrtc.org>
Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#21702}
ShiftMediaProject/libilbc,ShiftMediaProject/libilbc,TimothyGu/libilbc,TimothyGu/libilbc,ShiftMediaProject/libilbc,TimothyGu/libilbc,ShiftMediaProject/libilbc,TimothyGu/libilbc,TimothyGu/libilbc,ShiftMediaProject/libilbc