It is now possible to call qt_add_big_resources with multiple .qrc files
that are in different directories but have the same file name.
Before, this resulted in target name conflict errors.
Pick-to: 6.1
Fixes: QTBUG-93230
Change-Id: Ic3d9d6974a107163aeb7ada0b6f1fa113fb18de0
Reviewed-by: Alexandru Croitor <alexandru.croitor@qt.io>
