Qt Quick compiler builds failed to load the images if everything
was under the same qresource tag. Possibly some generated structure
got too large.

Change-Id: I17494189658fa7fee3a5ae82f56ca622d0a91098
Reviewed-by: Titta Heikkala <titta.heikkala@theqtcompany.com>
Reviewed-by: Tomi Korpipää <tomi.korpipaa@theqtcompany.com>
Reviewed-by: Pasi Keränen <pasi.keranen@digia.com>