GrandCentral: put interface before the XMR's.

Thanks @seldridge!

Author: dtzSiFive

lib/Dialect/FIRRTL/Transforms/GrandCentral.cpp

@@ -2595,7 +2595,8 @@ void GrandCentralPass::runOnOperation() {
 
     interfaceVec.push_back(topIface);
 
-    // Instantiate the interface inside the companion.
+    // Instantiate the interface before the view and the XMR's we inserted above.
+    viewBuilder.setInsertionPoint(view);
     viewBuilder.create<sv::InterfaceInstanceOp>(
         topIface.getInterfaceType(), view.getName(),
         // TODO: Proper inner sym namespace handling