Fix parsing of arc elements in paths
The arc element takes some flag parameters, which could be mixed up with the float parameters since svg does not require delimiting characters here. Hence legal svg would be misread..
Fixes: QTBUG-92184
Pick-to: 6.2 6.1 5.15
Change-Id: I5885c50d47e2e06ab0f02afefb7a5585c5c713ff
Reviewed-by: Paul Olav Tvete paul.tvete@qt.io
(cherry picked from commit b313862f)