RFR : 7076487 : (sctp) SCTP API classes does not exist in JDK for Mac

[Seán Coffey]

Looking to backport this one to jdk7u-dev. Given the different build 
system, the make logic is different.

bug ID : https://bugs.openjdk.java.net/browse/JDK-7076487
webrev : http://cr.openjdk.java.net/~coffeys/webrev.7076487.7u/webrev/
The fix is same as the windows approach where we basically throw 
UnsupportedOperationException for SCTP operations. The sctp tests on Mac 
OSX run ok and throw the exception as expected.

regards,
Sean.