Review 27720

C. Thomas Tyler
Fixed issue preventing systemd service checks from working.

Expanded scope of systemd checks to include any services related to
the instance based on namving convention (p4*_N*.service), in addition
to the checks for the 3 standard services (p4d_N/p4broker_N/p4p_N).
This would include, for example, p4dtg_1.
Tip: Use n and p to cycle through the changes.