RDKB-61922: RDK Coverity cleanup for dmcli

[rajkamal-cv]

Reason for change: Address Coverity issues in MsgBusTestServer executable
Test Procedure: Run MsgBusTestServer and MsgBusTestClient and check for errors
Risks: Low
Priority: P1

[rajkamal-cv]

1. Is this a Bug or a User Story (US)? RDKB-61922 is User Story
2. If it is a User Story:
   • Have all dependent PRs from other components been listed (if any)?
     • No Dependent PRs
   • Does the commit message include both the User Story ticket and the Subtask ticket?
     • Yes. Commit msg has the User Story ticket - RDKB-61922: RDK Coverity cleanup for dmcli
   • Will be all changes related to the User Story squashed and merged in a single commit?
     • Yes
   • Has the PR been raised only after completing all changes for the User Story (no partial changes)?
     • Yes
   • Has code development for the User Story been completed? Yes
     • If yes, has the Gerrit topic or list of all dependent PRs across components (including meta-layer changes) been shared? - https://gerrit.teamccp.com/#/q/topic:RDKB-61922+(status:open+OR+status:merged)
3. Is there a validation log available in the Jira ticket for verifying builds with the updated generic-srcrev.inc across all platforms?
   • If yes, have the links to validation comments been shared? format
     Yes. Logs are available here - https://ccp.sys.comcast.net/browse/RDKB-61922?focusedId=24177745&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-24177745