Using QStringLiteral to compare strings performs poorly
compared to QLatin1String.
These cases were previously fixed by commit 1a5c0b26, but
some were reintroduced with new commits to QDoc.
Change-Id: I272376052e876d88817606deb0a6dda92867dcbf
Reviewed-by: Kai Koehne <kai.koehne@theqtcompany.com>