[FS#1052] dnsmasq hotplug script does not work inside ujail

[LEDE Bugs]

A new Flyspray task has been opened.  Details are below. 

User who did this - Nathaniel Wesley Filardo (nwf) 

Attached to Project - LEDE Project
Summary - dnsmasq hotplug script does not work inside ujail
Task Type - Bug Report
Category - Base system
Status - Unconfirmed
Assigned To - 
Operating System - All
Severity - Low
Priority - Very Low
Reported Version - Trunk
Due in Version - Undecided
Due Date - Undecided
Details - Testing b73986a8264016883a8a7d666687a340cb810934 on ipq806x (C2600, specifically), using dnsmasq inside ujail fails to run hotplug events because /lib/functions.sh is unavailable inside the jail:

Mon Oct  9 20:13:53 2017 daemon.debug dnsmasq-script[1]: /sbin/hotplug-call: .: line 6: can't open '/lib/functions.sh'
Mon Oct  9 20:13:53 2017 daemon.warn dnsmasq[1]: script process exited with status 2

Unfortunately, the fix is not as simple as adding /lib/functions.sh to the jail mount, as that results in the uninformative

Mon Oct  9 20:15:35 2017 daemon.warn dnsmasq[1]: script process exited with status 1

Suggestions?

More information can be found at the following URL:
https://bugs.lede-project.org/index.php?do=details&task_id=1052