Reformat license variable to match the other perl specifications.

perl/perl.spec

@@ -31,7 +31,7 @@ Vendor:       The Perl Project
 Packager:     The OpenPKG Project
 Distribution: OpenPKG [REL]
 Group:        Language
-License:      Artistic or GPL
+License:      GPL/Artistic
 Version:      5.6.1
 Release:      20020510