Amlogic修改桌面壁纸
平台：A311D Android9.0
将自定义壁纸放在覆盖壁纸目录下即可
系统默认壁纸目录
frameworks/base/core/res/res/drawable-nodpi/default_wallpaper.png
frameworks/base/core/res/res/drawable-sw600dp-nodpi/default_wallpaper.png
frameworks/base/core/res/res/drawable-sw720dp-nodpi/default_wallpaper.png
覆盖壁纸目录
device/amlogic/w400/overlay/frameworks/base/core/res/res/drawable-nodpi/default_wallpaper.png
device/amlogic/w400/overlay/frameworks/base/core/res/res/drawable-sw600dp-nodpi/default_wallpaper.png
device/amlogic/w400/overlay/frameworks/base/core/res/res/drawable-sw720dp-nodpi/default_wallpaper.png
