Log Message:
Starting with ExtUtils::MakeMaker 6.43 some public variables (esp.
Recognized_Att_Keys) were made private, which broke SpamAssassin's
(ab)use of those variables. For details see
https://issues.apache.org/SpamAssassin/show_bug.cgi?id=6131.

Perl 5.10.1 includes ExtUtils::MakeMaker 6.55_2 and consequently building
SpamAssassin 3.2.5 with DESTDIR support in pkgsrc does not work anymore.

The fix changes the decision whether the used EU::MM module has good
enough DESTDIR support to depend only on the version number
(ie. mm_has_good_destdir is true) instead of the availability of the
key 'DESTDIR' in the (now non-public) Recognized_Att_Keys hash.

Ok to commit during freeze by wiz@