Remove recipes providing sllin configuration for the full demo,
as all LIN usage is being replaced with CAN. The recipes for the
sllin driver and associated lin_config utility are kept for now in
case there are external uses.
Bug-AGL: SPEC-4635
Change-Id: I67b7acf5a8c3801cb1890ee27486080255252385 Signed-off-by: Scott Murray <scott.murray@konsulko.com>