vg_load_svg: Add points copy of missing polygon/polyline

vg_load_svg: Add points copy of missing polygon/polyline

Summary:
When using <use> node, do atrribute copy.
At that time, when target(url) is polygon or polyline,
points array is not copied, causing a problem in output.
So, add missing array copy.

Test Plan:
 - Test SVG code

<svg version="1.1" id="Layer_1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" x="0px" y="0px"
viewBox="0 0 64 64" enable-background="new 0 0 64 64" xml:space="preserve">
    <g opacity="0.5">
        <defs>
            <polygon id="test" opacity="0.5" points="41.8,14.5 22.2,14.5 22.2,22.8 41.8,40.7"/>
        </defs>
        <use xlink:href="#test"  overflow="visible"/>
    </g>
</svg>

Reviewers: Hermet, smohanty

Reviewed By: Hermet

Subscribers: #reviewers, #committers, kimcinoo, herb, cedric

Tags: #efl

Differential Revision: https://phab.enlightenment.org/D12174

Change-Id: Iecbed3a953d7e7465b54e9c648474ca8f9480e0a