Executable path retrieval moved to security-server

Executable path retrieval moved to security-server

[Issue#] SSDWSSP-274
[Feature/Bug] N/A
[Problem] security_server_check_privilege_by_sockfd should not require root privileges
[Cause] The function reads /proc/[pid]/exe
[Solution] Executable retrieval moved to security-server.

[Verification] Build & install. Run security-server-tests-client-smack --regexp=tc06_check_privilege_by_sockfd
Security server logs should contain valid executable path in lines starting with SS_SMACK

Change-Id: Ib06414e80c9ee992108b7c49b33914e9047e5871