remarkable: fix fbdepth use in startup script (#6658)

The reMarkable version of fbdepth doesn't support the -1 rotation so
this was actually not setting the rotation at all. I didn't notice this
as I was always launching koreader from xochitl so the rotation was
already set correctly.

platform/remarkable/koreader.sh

@@ -108,7 +108,7 @@ ko_do_fbdepth() {
         # Swap to 8bpp if things look sane
         if [ -n "${ORIG_FB_BPP}" ]; then
             echo "Switching fb bitdepth to 8bpp & rotation to Portrait" >>crash.log 2>&1
-            ./fbdepth -d 8 -r -1 >>crash.log 2>&1
+            ./fbdepth -d 8 -r 1 >>crash.log 2>&1
         fi
     fi
 }