HLSL: ignore geometry attributes on non-GS stages.

If a shader includes a mixture of several stages, such as HS and GS,
the non-stage output geometry should be ignored, lest it conflict
with the stage output.

hlsl/hlslParseHelper.cpp

@@ -8559,6 +8559,11 @@ bool HlslParseContext::handleInputGeometry(const TSourceLoc& loc, const TLayoutG
 //
 bool HlslParseContext::handleOutputGeometry(const TSourceLoc& loc, const TLayoutGeometry& geometry)
 {
+    // If this is not a geometry shader, ignore.  It might be a mixed shader including several stages.
+    // Since that's an OK situation, return true for success.
+    if (language != EShLangGeometry)
+        return true;
+
     switch (geometry) {
     case ElgPoints:
     case ElgLineStrip: