QMimeDatabase: fix detection of pattern conflict in different prefixes
Installing a second mimetype with *.txt as glob had a different effect depending on whether it was installed into the same prefix or a different prefix as the one where text/plain is installed.
Pick-to: 6.6 Change-Id: I7f54b8efe22f620eb57257745c48fe5402c87626 Reviewed-by: Thiago Macieira thiago.macieira@intel.com (based on commit 1b39e61a)