proc: Fix off-by-one accessing device on start
    
    If we start with position other than 0, we would be accessing the *next*
    device to print, and the procfs output would be wrong. This can be
    observed by printing the proc file using small reads, such as:
    
      dd if=/proc/datto-info bs=32 status=none
    
    Fix the off-by-one array access.