Fix Onyx Boox black screen on wake by not using SurfaceView (koreader#579)

On some Onyx Boox devices (confirmed on Palma 2), the SurfaceView
surface is not recreated after the rapid RESUME/PAUSE/STOP activity
cycling that the Boox system performs on wake. This leaves
android.app.window permanently nil, causing a black screen.

The SurfaceView with setZOrderOnTop(true) and PixelFormat.TRANSPARENT
was introduced for NGL4/Tolino devices. The Onyx Qualcomm EPD API
(View.refreshScreen) does not require a SurfaceView — when needsView is
false, einkUpdate() already falls back to the DecorView content view.
Setting needsView()=false makes Onyx devices use NativeActivity's
default DecorView surface, which follows the standard activity lifecycle
and correctly survives the Boox wake sequence.

Author: msk

app/src/main/java/org/koreader/launcher/device/epd/OnyxEPDController.kt

@@ -48,7 +48,7 @@ class OnyxEPDController : QualcommEPDController(), EPDInterface {
     }
 
     override fun needsView(): Boolean {
-        return true
+        return false
     }
 
     override fun setEpdMode(targetView: android.view.View,