ticket:10144 merge of r33720 from ticket:9904 fix for enumset.h build on windows

git-svn-id: http://source.icu-project.org/repos/icu/icu@33732 251d0590-4201-4cf1-90de-194747b24ca1
ticket:10144 tag milestone:51.2 C

git-svn-id: http://source.icu-project.org/repos/icu/icu@33733 251d0590-4201-4cf1-90de-194747b24ca1