Do not draw the cursor

A compositor will take care of rendering the Wayland cursor surface
thus it won't need the window system cursor.

README.md

@@ -287,6 +287,11 @@ plugin:
   integration plugin file name without path and extension (for example
   "kms" for the DRM/KMS integration, "brcm" for Broadcom etc...).
 
+* **GREENISLAND_QPA_SHOW_CURSOR:** By default the mouse cursor is not
+  drawed because a compositor is expected to render the Wayland cursor
+  surface, set this variable to 1 if you want to draw the Green Island
+  cursor.
+
 ## Logging categories
 
 Qt 5.2 introduced logging categories and Hawaii takes advantage of

plugins/egldeviceintegration/kms/eglfskmsdevice.cpp

@@ -458,7 +458,7 @@ void EglFSKmsDevice::createScreens()
         Q_FOREACH (QPlatformScreen *screen, siblings)
             static_cast<EglFSKmsScreen *>(screen)->setVirtualSiblings(siblings);
 
-        if (primaryScreen)
+        if (primaryScreen && qEnvironmentVariableIsSet("GREENISLAND_QPA_SHOW_CURSOR"))
             m_globalCursor = new EglFSKmsCursor(primaryScreen);
     }
 }