Changes

sctp_{client,server}: disable Nagle by setting sctp_nodelay

The Nagle's algorithm [1] works by combining a number of small outgoing
messages and sending them all at once.  It's enabled by default when
opening a socket.  While it helps to reduce the network congestion by
reducing the number of outgoing packets, it comes at the cost of
increased delay.  Disable it by setting sctp_nodelay to true.

[1] https://en.wikipedia.org/wiki/Nagle%27s_algorithm

Change-Id: I6058a593a617d67d479eea0673d899a5da2d49bf
Related: SYS#7288