elementary image zoomable: fix non supported oversized image.

elementary image zoomable: fix non supported oversized image.

Summary:
if image size is larger than system support, photocam can not show the image.

Not like other types of image, photocam is originally designed for huge-size of image,
this result is not allowed by users, we should avoid the worst case as we can do.

This might not be the best idea, so you can improve it if you have a better solution.

Reviewers: kimcinoo

Reviewed By: kimcinoo

Subscribers: cedric, #reviewers, #committers

Tags: #efl

Differential Revision: https://phab.enlightenment.org/D12164

Change-Id: I6e542227062dae8d42fd870d1e6a69a935df5d12