PocketBook: handle rendering of interface and books directly with inkview (#8727)

Use ffi/framebuffer_pocketbook.lua, using Pocketbooks's own
inkview library for framebuffer interactions.

base

@@ -1 +1 @@
-Subproject commit 9548f1fc0a5010b2383058d005572c2919702c4a
+Subproject commit fb7610cf114f19eec6010121b2e262d727ec3c08

frontend/device/pocketbook/device.lua

@@ -101,7 +101,7 @@ function PocketBook:init()
     local raw_input = self.raw_input
     local touch_rotation = raw_input and raw_input.touch_rotation or 0
 
-    self.screen = require("ffi/framebuffer_mxcfb"):new {
+    self.screen = require("ffi/framebuffer_pocketbook"):new {
         device = self,
         debug = logger.dbg,
         wf_level = G_reader_settings:readSetting("wf_level") or 0,
@@ -596,6 +596,12 @@ local PocketBook741 = PocketBook:new{
     usingForcedRotation = landscape_ccw,
 }
 
+
+function PocketBook741._fb_init(fb, finfo, vinfo)
+    -- Pocketbook Color Lux reports bits_per_pixel = 8, but actually uses an RGB24 framebuffer
+    vinfo.bits_per_pixel = 24
+end
+
 -- PocketBook Color Lux (801)
 local PocketBookColorLux = PocketBook:new{
     model = "PBColorLux",