Don't restore Viewport 0 if it hasn't been set yet. (#3219)

Fixes a driver crash when starting some games caused by #3217

Ryujinx.Graphics.OpenGL/Pipeline.cs

@@ -612,7 +612,7 @@ namespace Ryujinx.Graphics.OpenGL
                     _program?.Bind();
                     _unit0Sampler?.Bind(0);
 
-                    GL.ViewportArray(0, 1, _viewportArray);
+                    RestoreViewport0();
 
                     Enable(EnableCap.CullFace, _cullEnable);
                     Enable(EnableCap.StencilTest, _stencilTestEnable);
@@ -1500,9 +1500,12 @@ namespace Ryujinx.Graphics.OpenGL
         }
 
         public void RestoreViewport0()
+        {
+            if (_viewportArray.Length > 0)
             {
                 GL.ViewportArray(0, 1, _viewportArray);
             }
+        }
 
         public bool TryHostConditionalRendering(ICounterEvent value, ulong compare, bool isEqual)
         {