proc_mutex-unix: follow up to r1733775.
Restore mmap-ed fd close stripped by above commit.


git-svn-id: https://svn.apache.org/repos/asf/apr/apr/trunk@1738791 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/locks/unix/proc_mutex.c b/locks/unix/proc_mutex.c
index 9b623c6..2edeed3 100644
--- a/locks/unix/proc_mutex.c
+++ b/locks/unix/proc_mutex.c
@@ -513,8 +513,9 @@
         close(fd);
         return rv;
     }
-    new_mutex->pthread_refcounting = 1;
+    close(fd);
 
+    new_mutex->pthread_refcounting = 1;
     new_mutex->curr_locked = -1; /* until the mutex has been created */
 
     if ((rv = pthread_mutexattr_init(&mattr))) {