export DISPLAY.

* src/testsuite/x11-1-test: export DISPLAY.
* src/testsuite/x11-5-test: Likewise.

* src/testsuite/x11-5-test: Use $XMODMAP.

Rev: src/testsuite/x11-1-test:1.5
Rev: src/testsuite/x11-2-test:1.6
Rev: src/testsuite/x11-5-test:1.4