Fix #113811: Blender freezes upon adding a Cryptomatte node

Blender freezes when adding a Cryptomatte node and using the GPU
compositor, even if the node is later removed.

This was because the CPU compositor acquired a render result mutex and
never released it due to an early exit that missed that release. This
patch fixes that by adding an appropriate release in that early exist.

source/blender/compositor/nodes/COM_CryptomatteNode.cc

@@ -104,6 +104,9 @@ void CryptomatteNode::input_operations_from_render_source(
   RenderResult *render_result = render ? RE_AcquireResultRead(render) : nullptr;
 
   if (!render_result) {
+    if (render) {
+      RE_ReleaseResult(render);
+    }
     return;
   }