VoCore2: new firmware 20190422

Now new firmware is ready at http://vonger.cn/misc/vocore2/20190422.bin

new firmware is ready at http://vonger.cn/misc/vocore2/20190422.bin
 
New features for VoCore2 and its screen
 
– add ext4 driver to firmware.
– add librt to firmware.
– default support Qt/GDB debug.
– add framebuffer driver and fbcon for console to firmware.
– add dosbox/libsdl makefile to vocore2 github.
– new vocore2 banner in firmware.
– add vocore2 screen driver support to screen sdk.
– add keyboard support to DOOM demo in screen sdk.
 
Bug Fix:
 
– fix audio record issue in 44.1kHz.
– fix feeds source duplicated.
– fix some spell mistake on github.