UpdateHub Might Dereference An Uninitialized Pointer

In updatehub_probe, right after JSON parsing is complete, objects\[1] is accessed from the output structure in two different places. If the JSON contained less than two elements, this access would reference unitialized stack memory. This could result in a crash, denial of service, or possibly an information leak. Provided the fix in CVE-2020-10059 is applied, the attack requires compromise of the server. See NCC-ZEP-030 This issue affects: zephyrproject-rtos zephyr version 2.1.0 and later versions. version 2.2.0 and later versions.