Fix #6398 for DX9 as well

GPU/Directx9/TransformPipelineDX9.cpp

@@ -433,6 +433,12 @@ void TransformDrawEngineDX9::DecodeVertsStep() {
 		}
 
 		const int vertexCount = indexUpperBound - indexLowerBound + 1;
+
+		// This check is a workaround for Pangya Fantasy Golf, which sends bogus index data when switching items in "My Room" sometimes.
+		if (decodedVerts_ + vertexCount > VERTEX_BUFFER_MAX) {
+			return;
+		}
+
 		// 3. Decode that range of vertex data.
 		dec_->DecodeVerts(decoded + decodedVerts_ * (int)dec_->GetDecVtxFmt().stride,
 			dc.verts, indexLowerBound, indexUpperBound);