sysfs_extractor: fixed pulled files verification.
sysfs_extractor: fixed pulled files verification.

When no files are listed for one the specified directoris, the
instrument checks whether there are any files in that directory on the
device. If that directory itself does not exist; that will result in an
error. This is now handled correctly.

ARM-software/workload-automation,bjackman/workload-automation,muendelezaji/workload-automation,lisatn/workload-automation,chase-qi/workload-automation,setrofim/workload-automation,bjackman/workload-automation,Sticklyman1936/workload-automation,ep1cman/workload-automation,bathepawan/workload-automation,jimboatarm/workload-automation,jimboatarm/workload-automation,chase-qi/workload-automation,chase-qi/workload-automation,Sticklyman1936/workload-automation,muendelezaji/workload-automation,bathepawan/workload-automation,muendelezaji/workload-automation,bathepawan/workload-automation,bathepawan/workload-automation,Sticklyman1936/workload-automation,ep1cman/workload-automation,ep1cman/workload-automation,muendelezaji/workload-automation,jimboatarm/workload-automation,setrofim/workload-automation,ep1cman/workload-automation,jimboatarm/workload-automation,bjackman/workload-automation,bjackman/workload-automation,lisatn/workload-automation,jimboatarm/workload-automation,ARM-software/workload-automation,ep1cman/workload-automation,jimboatarm/workload-automation,ARM-software/workload-automation,ARM-software/workload-automation,lisatn/workload-automation,chase-qi/workload-automation,Sticklyman1936/workload-automation,setrofim/workload-automation,bathepawan/workload-automation,setrofim/workload-automation,chase-qi/workload-automation,Sticklyman1936/workload-automation,bathepawan/workload-automation,chase-qi/workload-automation,lisatn/workload-automation,ep1cman/workload-automation,muendelezaji/workload-automation,Sticklyman1936/workload-automation,bjackman/workload-automation,bjackman/workload-automation,muendelezaji/workload-automation