Unique device names
Unique device names

Since BRW, test SdkBackupFolder cannot create duplicated device folders.
However, the previous test SdkDeviceNames always set the same device
name for all devices. So as soon as Jenkins runs on more than one
machine with the same account, the SdkBackupFolder fails.

meganz/sdk,meganz/sdk,meganz/sdk,meganz/sdk,meganz/sdk,meganz/sdk,meganz/sdk