Remove the THREADS_HAVE_PIDS hint for NTPL-enabled Linux
systems.  Otherwise ppids are cached too aggressively,
resulting in broken behavior.

--- perl-5.8.0/hints/linux.sh.nptl	2004-12-01 12:38:16.021664783 -0500
+++ perl-5.8.0/hints/linux.sh	2004-12-01 12:38:28.213470553 -0500
@@ -249,7 +249,7 @@
 cat > UU/usethreads.cbu <<'EOCBU'
 case "$usethreads" in
 $define|true|[yY]*)
-        ccflags="-D_REENTRANT -D_GNU_SOURCE -DTHREADS_HAVE_PIDS $ccflags"
+        ccflags="-D_REENTRANT -D_GNU_SOURCE $ccflags"
         set `echo X "$libswanted "| sed -e 's/ c / pthread c /'`
         shift
         libswanted="$*"