Legacy cleanup, part 2 (#3659)

* Legacy cleanup, part 2

There are still things that can be removed, those will be likely done in part three:
`The Return of the Cleanup` :)

Signed-off-by: nemerle <96597+nemerle@users.noreply.github.com>

* Fix windows build

Somehow there were some unfixed errors from enabled warnings?
I'm unsure if I've pulled repo in unstable state, or those were somehow
missed.

Signed-off-by: nemerle <96597+nemerle@users.noreply.github.com>

Code/Editor/EditorViewportWidget.cpp

@@ -54,7 +54,6 @@
 // CryCommon
 #include <CryCommon/HMDBus.h>
 #include <CryCommon/IRenderAuxGeom.h>
-#include <CryCommon/physinterface.h>
 
 // AzFramework
 #include <AzFramework/Render/IntersectorInterface.h>
@@ -70,7 +69,6 @@
 #include "Include/IDisplayViewport.h"
 #include "Objects/ObjectManager.h"
 #include "ProcessInfo.h"
-#include "IPostEffectGroup.h"
 #include "EditorPreferencesPageGeneral.h"
 #include "ViewportManipulatorController.h"
 #include "EditorViewportSettings.h"
@@ -100,7 +98,6 @@
 #include <QtGui/private/qhighdpiscaling_p.h>
 
 #include <IEntityRenderState.h>
-#include <IPhysics.h>
 #include <IStatObj.h>
 
 AZ_CVAR(