remarkable FW 2.6: use explicit busybox for 'sync' (#7509)
remarkable FW 2.6: use explicit busybox for 'sync' (#7509)


NiLuJe/koreader,Frenzie/koreader,Frenzie/koreader,mwoz123/koreader,NiLuJe/koreader,koreader/koreader,poire-z/koreader,koreader/koreader,poire-z/koreader