[Coverity CID :196639]Error handling issues in /samples/bluetooth/ipsp/src/main.c

[aasthagr]

Static code scan issues seen in File: /samples/bluetooth/ipsp/src/main.c
Category: Error handling issues
Function: build_reply
Component: Samples
CID: 196639
Please fix or provide comments to square it off in coverity in the link: https://scan9.coverity.com/reports.htm#v32951/p12996

[Vudentz]

@tbursztyka Im fixing it