Fix accessing MTP devices without FriendlyName with libmtp 1.1.19
In libmtp 1.1.19, an empty string is returned instead of NULL for devices without a deviceName, which breaks accessing those devices with kio-mtp
Edited by Antonio Rojas
In libmtp 1.1.19, an empty string is returned instead of NULL for devices without a deviceName, which breaks accessing those devices with kio-mtp