RFR: JDK-8161360,,Deprecated vfork() should not be used on Solaris

[Alan Burlison]

vfork(2) is deprecated on Solaris and using it generates compiler 
warnings. When compiled with warnings-as-errors, this results in 
compilation failures.

Bug:    https://bugs.openjdk.java.net/browse/JDK-8161360
Webrev: http://cr.openjdk.java.net/~alanbur/JDK-8161360
Thanks,

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Alan Burlison
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