RFR(XS): 8035394: PPC64: Make usage of intrinsic dsqrt depend on processor recognition.

[Lindenmaier, Goetz]

Hi,

Only some PPC processors have a sqrt instruction.

Currently, intrinsic for dsqrt is used if a corresponding rule is implemented in the .ad file (has_match_rule()).
Instead, call match_ruole_supported(), which allows to check processor properties.

Also adapt PPC64 .ad file to this.

Please review and test this change
http://cr.openjdk.java.net/~goetz/webrevs/8035394-1-fltRck/

It also needs to go to jdk8u via ppc-aix-port/stage.

Best regards,
  Goetz.