[REQUEST] Silabs EmberZNet 6.10.7.0 Zigbee NCP firmware images for Elelabs adapters

[Hedda]

Silicon Labs EmberZNet version 6.10.7.0 is the latest bug-fix release in the 6.10 series so should be the latest stable in that series.

https://www.silabs.com/documents/public/release-notes/emberznet-release-notes-6.10.7.0.pdf

@NilsBohr Like to request you add EmberZNet 6.10.7.0 Zigbee NCP firmware images (as upgrade for existing 6.10.3.0 images).

(That should keep all existing compatibility and could act as a "stable" stop-gap while experimenting with 7.x series firmware).

Fixed in release 6.10.7.0

ID #	Description
398694, 823888, 519731	ZCL reporting plugin is modified so that a rarely occurring exception condition (failure to read a reportable attribute's value; possibly because the attribute's endpoint is disabled) does not result in excess execution cycles, repetitive printing of a debug message, and (for an RTOS configuration) blocking of a lower-priority task.
841499	Fixed issue where a newly joined device can sometimes not get added to the child table if its IEEE address is not known.
1150905	Fixed spurious frame pending bit set when there is no data pending.

Fixed in release 6.10.5.0

ID #	Description
1103581	Fixed an issue that caused a new device to join the network with a random extended PAN Id instead of using the same from received beacon. This difference in extended PAN Id was causing a PAN Id conflict upon device join.

[Hedda]

Closing in favor of #44