Use pkgsrc's patch to fix build
The subversion port was upgraded to version 1.9. devel/kdesdk4-kioslaves fails
to build against it now.
pkgsrc has a patch that fixes this issue in
of their repository. Add this patch.
Approved by: rakuco (mentor)
Obtained from: pkgsrc
Differential Revision: https://reviews.freebsd.org/D4002