framebuffer: simplify orientation (#1127)
framebuffer: simplify orientation (#1127)

depends on koreader/koreader#6309
koreader/koreader-base,koreader/koreader-base,koreader/koreader-base,NiLuJe/koreader-base,Frenzie/koreader-base,koreader/koreader-base,NiLuJe/koreader-base,Frenzie/koreader-base,Frenzie/koreader-base,Frenzie/koreader-base,NiLuJe/koreader-base,NiLuJe/koreader-base