Return correct error on name collision when creating new named
objects.
Check for correct error in affected places.

diff --git a/server/mutex.c b/server/mutex.c
index 3d887fb..09186ca 100644
--- a/server/mutex.c
+++ b/server/mutex.c
@@ -68,7 +68,7 @@
 
     if ((mutex = create_named_object( sync_namespace, &mutex_ops, name, attr )))
     {
-        if (get_error() != STATUS_OBJECT_NAME_COLLISION)
+        if (get_error() != STATUS_OBJECT_NAME_EXISTS)
         {
             /* initialize it if it didn't already exist */
             mutex->count = 0;