Wrong partition name used for devices ending with numbers

On Linux when a block device ends with a number (like my SD card device: **/dev/mmcblk0**) the first partition is called **/dev/mmcblk0p1** (with an added **p**). This snippet makes sure that the correct partition name is used in both cases.
Merge pull request #2216 from dagwieers/livestick-part-fix

Wrong partition name used for devices ending with numbers