ci: travis: switch mingw cross build to also use Fedora 29 as base
Summary:
The new image also contains the ewpi install in a different location.
Updating the references here.
Reviewers: bu5hm4n, zmike
Reviewed By: zmike
Subscribers: cedric, reviewers, committers
Tags: efl
Differential Revision: https://phab.enlightenment.org/D7833