From: Fabian Vogt <fabian@ritter-vogt.de>
Subject: Fix no return in nonvoid function error

Optflags include -Werror=return-type, which does not like qt3d without this.

Index: qt3d-everywhere-src-5.14.0-alpha/src/render/renderers/opengl/graphicshelpers/imagesubmissioncontext.cpp
===================================================================
--- qt3d-everywhere-src-5.14.0-alpha.orig/src/render/renderers/opengl/graphicshelpers/imagesubmissioncontext.cpp
+++ qt3d-everywhere-src-5.14.0-alpha/src/render/renderers/opengl/graphicshelpers/imagesubmissioncontext.cpp
@@ -73,6 +73,9 @@ GLenum glAccessEnumForShaderImageAccess(
         return GL_WRITE_ONLY;
     case QShaderImage::ReadWrite:
         return GL_READ_WRITE;
+    default:
+        Q_UNREACHABLE();
+        return GL_NONE;
     }
 }