ecore_evas: Fix elm warnings when building without wayland support

ecore_evas: Fix elm warnings when building without wayland support

Summary:
efl_ui_win.c only includes private ecore_evas headers when building
for wayland, but wayland canvas creation functions are called even
in non-wayland builds.

Move the "hidden" wayland APIs to the public header so they don't
mess up non-wayland builds.

Reviewers: devilhorns, zmike

Reviewed By: devilhorns, zmike

Subscribers: devilhorns, cedric, #reviewers, #committers, zmike

Tags: #efl

Differential Revision: https://phab.enlightenment.org/D6822