Revert "pppoe: do not check manually if pppoe process runs"
Revert "pppoe: do not check manually if pppoe process runs"

This reverts commit f0b453c6709b2830d04981c09ec4075b978a5427.

Test was right - pppd did not run (it was a bug T2488)

vyos/vyos-1x,vyos/vyos-1x,vyos/vyos-1x,vyos/vyos-1x