Feature/kbd drop

Drop the temporary kbd package because the upstream package has been updated to include the busybox fix (https://git.alpinelinux.org/aports/commit/main/kbd?id=81189e08a0c497a44660eb479120917291a67776)

I've tested it by rebuilding the n900 device package, which will re-create the keymaps using the loadkeys tool.

While testing with the xfce4 ui, I've noticed the wrong background, so I've added a commit to also fix it.