[FS#516] procd doesn't wait for a process to quit during restart

[LEDE Bugs]

The following task is now closed:

FS#516 - procd doesn't wait for a process to quit during restart
User who did this - Stijn Tintel (stintel)

Reason for closing: Implemented
Additional comments about closing: Fixed in LEDE master: https://git.lede-project.org/946d1dfb

More information can be found at the following URL:
https://bugs.lede-project.org/index.php?do=details&task_id=516