[Coverity CID: 185283] Control flow issues in /subsys/fs/nffs_fs.c

[Shilpashree3lc-zz]

Static code scan issues seen in File: /subsys/fs/nffs_fs.c
Category: Control flow issues
Function: nffs_tell
Component: Other
CID: 185283
Please fix or provide comments to square it off in coverity in the link: https://scan9.coverity.com/reports.htm#v32951/p12996

[lpereira]

Fixed by #7068