drd: Make the code added in r13792 portable

git-svn-id: svn://svn.valgrind.org/valgrind/trunk@13794 a5019735-40e9-0310-863c-91ae7b9d1cf9
diff --git a/drd/drd_pthread_intercepts.c b/drd/drd_pthread_intercepts.c
index 325ad60..a2233d5 100644
--- a/drd/drd_pthread_intercepts.c
+++ b/drd/drd_pthread_intercepts.c
@@ -249,7 +249,8 @@
     * See also PTHREAD_MUTEX_KIND_MASK_NP in glibc source file
     * <nptl/pthreadP.h>.
     */
-   kind &= 3;
+   kind &= PTHREAD_MUTEX_RECURSIVE | PTHREAD_MUTEX_ERRORCHECK |
+      PTHREAD_MUTEX_NORMAL | PTHREAD_MUTEX_DEFAULT;
 
    if (kind == PTHREAD_MUTEX_RECURSIVE)
       return mutex_type_recursive_mutex;