Revert "Clean up usage of qtsvg as dependency"

Revert "Clean up usage of qtsvg as dependency"

qtdeclarative has a runtime dependency, some tests rely on the svg
module being available, so in order to not reduce the test coverage,
revert this change.
I'd like to see a better/cleaner separation, but for the time being,
better coverage wins.

This reverts commit fbd782636b6ee413d2b6e8bca408263297194254.

Change-Id: I60d6b585e25e2e7c4f6ad705b754279968827842
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>
Reviewed-by: Jędrzej Nowacki <jedrzej.nowacki@qt.io>
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@qt.io>