Fix compilation with clang
Summary: libkexiv2/src/kexiv2_p.cpp:726:9: error: token is not a valid binary operator in a preprocessor subexpression
Test Plan: Builds
Reviewers: Frameworks, cgilles, kfunk
Reviewed By: kfunk
Subscribers: kfunk
Differential Revision: https://phabricator.kde.org/D4179