Handle tspan x and y properties

Inkscape represents multi-line text with a <tspan> for each line, e.g.
<tspan sodipodi:role="line" id="..." style="..." x="10" y="25">line</tspan>
We now set the absolute position of each text run that has x and y
properties, unless we're restricted to Tiny1.2 features.

Fixes: QTBUG-11072
Fixes: QTBUG-122294
Fixes: QTBUG-149803
Change-Id: Ie30548d5c6191a256c11b2b0d4a6c07e9a610f18
Reviewed-by: Hatem ElKharashy <hatem.elkharashy@qt.io>