This fixes the breakage caused by "ivi-shell: make ivi-layout.c as a
part of ivi-shell.so"

hmi-controller.c:
A reference implementation of controller module does not use the layout
functions directly. This get function pointers at controller_module_init
which called by ivi-shell.

ivi-layout-export.h:
Definition of interfaces in a struction: ivi_controller_interface.
function pointers are set at ivi-layout.c.

ivi-layout-private.h:
Definition of some interfaces are remove bucause it is implemented in
ivi-layout.c and set it as function pointer. Several interfaces are kept
here because they are implemented in ivi-layout.c/transition.c but used
in other files.

ivi-layout-transition.c:
remove WL_EXPORT because export is not needed anymore.
remove unnesesary unsed method.

ivi-shell.c:
call controller_module_init of hmi-controller to init it and set
function pointers. If the interface_version is equal or
greater than what hmi_controller was built with, things are pass.
If the interface_version is smaller than what the controller expects,
it has to fail because it cannot work. This is followed the manner,

- never remove a function pointer
- never modify an existing function signature
- additions are allowed at the end of struct ivi_controller_interface
- all function pointers must always be populated and working in
  ivi-shell.so (ivi-layout.c etc.)

Signed-off-by: Nobuhiko Tanibata <NOBUHIKO_TANIBATA@xddp.denso.co.jp>
Acked-by: Pekka Paalanen <pekka.paalanen@collabora.co.uk>