iBasso DX50/DX90: Major code cleanup and reorganization.

Reorganization

- Separated iBasso devices from PLATFORM_ANDROID. These are now standlone
  hosted targets. Most device specific code is in the
  firmware/target/hosted/ibasso directory.
- No dependency on Android SDK, only the Android NDK is needed.
  32 bit Android NDK and Android API Level 16.
- Separate implementation for each device where feasible.

Code cleanup

- Rewrite of existing code, from simple reformat to complete reimplementation.
- New backlight interface, seperating backlight from touchscreen.
- Rewrite of device button handler, removing unneeded code and fixing memory
  leaks.
- New Debug messages interface logging to Android adb logcat (DEBUGF, panicf,
  logf).
- Rewrite of lcd device handler, removing unneeded code and fixing memory leaks.
- Rewrite of audiohw device handler/pcm interface, removing unneeded code and
  fixing memory leaks, enabling 44.1/48kHz pthreaded playback.
- Rewrite of power and powermng, proper shutdown, using batterylog results
  (see http://gerrit.rockbox.org/r/#/c/1047/).
- Rewrite of configure (Android NDK) and device specific config.
- Rewrite of the Android NDK specific Makefile.

Misc

- All plugins/games/demos activated.
- Update tinyalsa to latest from https://github.com/tinyalsa/tinyalsa.

Includes

- http://gerrit.rockbox.org/r/#/c/993/
- http://gerrit.rockbox.org/r/#/c/1010/
- http://gerrit.rockbox.org/r/#/c/1035/

Does not include http://gerrit.rockbox.org/r/#/c/1007/ due to new backlight
interface and new option for hold switch, touchscreen, physical button
interaction.

Rockbox needs the iBasso DX50/DX90 loader for startup, see
http://gerrit.rockbox.org/r/#/c/1099/

The loader expects Rockbox to be installed in /mnt/sdcard/.rockbox/. If
/mnt/sdcard/ is accessed as USB mass storage device, Rockbox will exit
gracefully and the loader will restart Rockbox on USB disconnect.

Tested on iBasso DX50.
Compiled (not tested) for iBasso DX90.
Compiled (not tested) for PLATFORM_ANDROID.

Change-Id: I5f5e22e68f5b4cf29c28e2b40b2c265f2beb7ab7

firmware/target/hosted/android/dx50/button-target.h

@@ -1,72 +0,0 @@
-/***************************************************************************
- *             __________               __   ___.
- *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
- *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
- *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
- *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
- *                     \/            \/     \/    \/            \/
- * $Id$
- *
- * Copyright (C) 2007 by Rob Purchase
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version 2
- * of the License, or (at your option) any later version.r
- *
- * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
- * KIND, either express or implied.
- *
- ****************************************************************************/
-
-#ifndef _BUTTON_TARGET_H_
-#define _BUTTON_TARGET_H_
-
-#include <stdbool.h>
-
-#define HAS_BUTTON_HOLD
-
-/* Main unit's buttons */
-#define BUTTON_LEFT        0x00000001
-#define BUTTON_RIGHT       0x00000002
-#define BUTTON_PLAY        0x00000004
-#define BUTTON_POWER       0x00000008
-#define BUTTON_VOL_UP      0x00000010
-#define BUTTON_VOL_DOWN    0x00000020
-#define BUTTON_POWER_LONG  0x00000040
-
-#define BUTTON_MAIN (BUTTON_LEFT|BUTTON_VOL_UP|BUTTON_VOL_DOWN\
-                    |BUTTON_RIGHT|BUTTON_PLAY|BUTTON_POWER|BUTTON_POWER_LONG)
-
-#define KEYCODE_LINEOUT 113
-#define KEYCODE_SPDIF 114
-#define KEYCODE_HOLD 115
-#define KEYCODE_PWR 116
-#define KEYCODE_PWR_LONG 117
-#define KEYCODE_SD 143
-#define KEYCODE_VOLPLUS 158
-#define KEYCODE_VOLMINUS 159
-#define KEYCODE_PREV 160
-#define KEYCODE_NEXT 162
-#define KEYCODE_PLAY 161
-#define STATE_UNLOCKED 16
-#define STATE_SPDIF_UNPLUGGED 32
-#define STATE_LINEOUT_UNPLUGGED 64
-
-/* Touch Screen Area Buttons */
-#define BUTTON_TOPLEFT      0x00001000
-#define BUTTON_TOPMIDDLE    0x00002000
-#define BUTTON_TOPRIGHT     0x00004000
-#define BUTTON_MIDLEFT      0x00008000
-#define BUTTON_CENTER       0x00010000
-#define BUTTON_MIDRIGHT     0x00020000
-#define BUTTON_BOTTOMLEFT   0x00040000
-#define BUTTON_BOTTOMMIDDLE 0x00080000
-#define BUTTON_BOTTOMRIGHT  0x00100000
-
-
-/* Software power-off */
-#define POWEROFF_BUTTON         BUTTON_POWER_LONG
-#define POWEROFF_COUNT          0
-
-#endif /* _BUTTON_TARGET_H_ */