Revert "werror: fix build in vcl"

This reverts commit 5191fcb1.
Earlier, better fix was 831c69f9

vcl/source/opengl/OpenGLContext.cxx

@@ -785,15 +785,11 @@ bool OpenGLContext::ImplInit()
             glXSwapInterval( 1 );
 
             if( errorTriggered )
-            {
                 SAL_WARN("vcl.opengl", "error when trying to set swap interval, NVIDIA or Mesa bug?");
-            }
             else
-            {
                 VCL_GL_INFO("vcl.opengl", "set swap interval to 1 (enable vsync)");
         }
     }
-    }
 
     bool bRet = InitGLEW();
     InitGLEWDebugging();
@@ -1363,7 +1359,6 @@ void OpenGLContext::makeCurrent()
 
     // move the context to the end of the contexts list
     static int nSwitch = 0;
-    (void) nSwitch; // -Werror=unused-variable
     VCL_GL_INFO("vcl.opengl", "******* CONTEXT SWITCH " << ++nSwitch << " *********");
     if( mpNextContext )
     {