x11/libXrandr: Update to 1.5.2

Update x11/libXrandr to 1.5.2
This is a maintenance release, containing fixes to the build system and
updates for the freedesktop.org gitlab move.

pet portlint by moving USES= earlier
INSTALL_TARGET=install-strip to strip binaries and libraries

Changelog:
https://lists.x.org/archives/xorg-announce/2019-March/002979.html

Sponsored by: B3 Init