[BUGFIX] Add support for PNG icons of the SVG Tree

When the pagetree (base on SVG tree) is having a custom icon based on a PNG
like a custom page tree icon, then the SVG tree does not show anything.

The patch fixes the SVG tree to support rendering of PNG icons.

Resolves: #83410
Releases: master
Change-Id: Ifdcc827bc073da4b8eabcc209d03ce55d8f0c94f
Reviewed-on: https://review.typo3.org/55192


Tested-by: TYPO3com <no-reply@typo3.com>
Reviewed-by: Andreas Fernandez <typo3@scripting-base.de>
Tested-by: Andreas Fernandez <typo3@scripting-base.de>
Reviewed-by: Georg Ringer <georg.ringer@gmail.com>
Tested-by: Georg Ringer <georg.ringer@gmail.com>