RFR - 8080776 Fix for illegal instruction crash

[bill pittore]

This small change adds an early initialization API to the VM_Version 
class. Before this change, some early VM initialization code was calling 
into platform specific code that executed machine instructions that are 
illegal on certain hardware. With this change a platform can determine 
the proper instructions to execute.

http://cr.openjdk.java.net/~bpittore/8080776/webrev.00/

thanks,
bill