RFR 8060256: The loop in Arguments::parse() can be enhanced

[Jiangli Zhou]

Hi,

This enhancement was suggested by Bertrand during the review for 
8047934. The 'continue' statement can be added to the matching cases to 
avoid the further checks after that.

   http://cr.openjdk.java.net/~jiangli/8060256/webrev.00/

Tested with jtreg hotspot/test/runtime/CommandLine tests, including the 
new one being added. Also started JPRT, no failure so far.

Thanks,
Jiangli