Most DRD regression tests are now skipped when LinuxThreads is detected. Removed LinuxThreads expected output files.

git-svn-id: svn://svn.valgrind.org/valgrind/trunk@7738 a5019735-40e9-0310-863c-91ae7b9d1cf9
diff --git a/exp-drd/tests/tc16_byterace.vgtest b/exp-drd/tests/tc16_byterace.vgtest
index a8bf0f1..2308aeb 100644
--- a/exp-drd/tests/tc16_byterace.vgtest
+++ b/exp-drd/tests/tc16_byterace.vgtest
@@ -1 +1,2 @@
+prereq: ./supported_libpthread
 prog: tc16_byterace