RFR(S): 8197906: Enable CDS mode execution of jtreg tests via make

[Mikhailo Seledtsov]

Please review this small change that enables execution of any jtreg 
test(s) in CDS mode
via make. Please see bug description for details.

Thanks to Erik and Igor for their help with this change.

     JBS: https://bugs.openjdk.java.net/browse/JDK-8197906
     WebRev: http://cr.openjdk.java.net/~mseledtsov/8197906.01/

     Testing:
       - ran hotspot_runtime in CDS mode with this change - Linux-x64 - 
no new failures
       - running several test sets in CDS mode via distributed test 
system - pass
       - running pre-integration sanity testing (HS tier1, tier2) - in 
progress

Thank you,
Misha