Merge pull request #7986 from hppritcha/topic/fix_issue7644

threads: fix a problem hit when using ex-hwloc

opal/mca/threads/pthreads/configure.m4

@@ -52,9 +52,9 @@ CFLAGS="$CFLAGS $THREAD_CFLAGS"
 CPPFLAGS_save="$CPPFLAGS"
 CPPFLAGS="$CPPFLAGS $THREAD_CPPFLAGS"
 LDFLAGS_save="$LDFLAGS"
-LDFLAGS="$LDFLAGS $THREAD_LDFLAGS"
+LDFLAGS="$THREAD_LDFLAGS"
 LIBS_save="$LIBS"
-LIBS="$LIBS $THREAD_LIBS"
+LIBS="$THREAD_LIBS"
 AC_RUN_IFELSE([AC_LANG_SOURCE([#include <pthread.h>
 #include <sys/types.h>
 #include <unistd.h>