Remove init-time GLES per-frame callback

The GLES renderer interface now allows the per-frame callback to be
registered after initialization. This change updates the emulator to
use the new interface. Since reading back completed frames is slow
(due to pipeline flush/stall), a future change will enable the
callback only while multitouch emulation is actually in use.

Change-Id: I7ad23b4bebe1bd3077863da4d50333cc0578519e
diff --git a/vl-android.c b/vl-android.c
index 1513541..f9afa5c 100644
--- a/vl-android.c
+++ b/vl-android.c
@@ -3877,15 +3877,8 @@
      * we just shut it down again once we have the strings. */
     {
         int qemu_gles = 0;
-
-        /* Set framebuffer change notification callback when starting
-         * GLES emulation. Currently only multi-touch emulation is
-         * interested in FB changes (to transmit them to the device), so
-         * the callback is set within MT emulation. */
         if (android_initOpenglesEmulation() == 0 &&
-            android_startOpenglesRenderer(android_hw->hw_lcd_width,
-                android_hw->hw_lcd_height,
-                multitouch_opengles_fb_update, NULL) == 0)
+            android_startOpenglesRenderer(android_hw->hw_lcd_width, android_hw->hw_lcd_height) == 0)
         {
             android_getOpenglesHardwareStrings(
                     android_gl_vendor, sizeof(android_gl_vendor),