Don't bypass fbdepth when starting KOReader @ 8bpp (#5841)

* [Kobo/reMarkable] Don't skip fbdepth when launching KOReader @ 8bpp

I'm not quite sure how that can happen unless you really want to, but
apparently it did on @Frenzie's H2O ;p

platform/kobo/koreader.sh

@@ -154,6 +154,7 @@ ORIG_FB_BPP="$(./fbdepth -g)"
 echo "Original fb bitdepth is set @ ${ORIG_FB_BPP}bpp" >>crash.log 2>&1
 # Sanity check...
 case "${ORIG_FB_BPP}" in
+    8) ;;
     16) ;;
     32) ;;
     *)

platform/remarkable/koreader.sh

@@ -85,6 +85,7 @@ echo "Original fb settings: bitdepth = ${ORIG_FB_BPP}, rotation = ${ORIG_FB_ROTA
 
 # Sanity check...
 case "${ORIG_FB_BPP}" in
+    8) ;;
     16) ;;
     32) ;;
     *)