give shadergen tags for the other two potential rendertargets for use down the line

Engine/source/shaderGen/shaderFeature.cpp

@@ -65,6 +65,14 @@ const char* ShaderFeature::getOutputTargetVarName( OutputTarget target ) const
       case RenderTarget3:
          targName = "col3";
          break;
+
+      case RenderTarget4:
+         targName = "col4";
+         break;
+
+      case RenderTarget5:
+         targName = "col5";
+         break;
    }
 
    return targName;
@@ -89,4 +97,4 @@ Var* ShaderFeature::findOrCreateLocal( const char *name,
 void ShaderFeature::setInstancingFormat(GFXVertexFormat *format)
 {
    mInstancingFormat = format;
-}
+}

Engine/source/shaderGen/shaderFeature.h

@@ -87,6 +87,8 @@ public:
       RenderTarget1 =   1 << 1,
       RenderTarget2 =   1 << 2,
       RenderTarget3 =   1 << 3,
+      RenderTarget4 =   1 << 4,
+      RenderTarget5 =   1 << 5,
    };
 
 protected: