RFR(S): 8204549: [aix][testbug] signal tests fail because vm can not start in primordial thread.

[Lindenmaier, Goetz]

Hi,

the signal tests implement a custom launcher that launches the VM in the primordial thread. 
This fails on aix. 
Exclude the tests on aix.

Please review. I recommend looking at the patch ... it's all the same ...
http://cr.openjdk.java.net/~goetz/wr18/8204549-aixPrimordial/01/

Best regards,
  Goetz.