[Coverity CID :191001]Control flow issues in /subsys/net/lib/lwm2m/lwm2m_rw_json.c

[mandarcthorat1]

Static code scan issues seen in File: /subsys/net/lib/lwm2m/lwm2m_rw_json.c
Category: Control flow issues
Function: put_json_postfix
Component: Networking
CID: 191001
Please fix or provide comments to square it off in coverity in the link: https://scan9.coverity.com/reports.htm#v32951/p12996

[galak]

Marked this resolved in coverity and merged #13755