ivi-shell: ivi-layout-export/private.h, reorgenize two interface from private to export because it is used by hmi-controller.c

Signed-off-by: Nobuhiko Tanibata <NOBUHIKO_TANIBATA@xddp.denso.co.jp>
ivi-shell: hmi-controller. avoid including ivi-layout-private.h

Signed-off-by: Nobuhiko Tanibata <NOBUHIKO_TANIBATA@xddp.denso.co.jp>