Change execute label to System to remove smack errors

Change execute label to System to remove smack errors

Jan 01 09:08:55 localhost audit[2765]: AVC lsm=SMACK fn=smack_key_permission action=denied subject="User" object="System::Privileged" requested=r pid=2765 comm="tlm-sessiond" key_serial=841328352 key_desc="_ses"
Jan 01 09:08:55 localhost audit[2765]: AVC lsm=SMACK fn=smack_inode_permission action=denied subject="User" object="System::Privileged" requested=r pid=2765 comm="tlm-sessiond" name="environ" dev="proc" ino=23193
Jan 01 09:08:55 localhost audit[2765]: AVC lsm=SMACK fn=smack_inode_permission action=denied subject="User" object="System::Privileged" requested=r pid=2765 comm="tlm-sessiond" name="sched" dev="proc" ino=23194
Jan 01 09:08:55 localhost audit[2765]: AVC lsm=SMACK fn=smack_key_permission action=denied subject="User" object="System::Privileged" requested=r pid=2765 comm="tlm-sessiond" key_serial=185875009 key_desc="_uid.5001"
Jan 01 09:08:55 localhost audit[2765]: AVC lsm=SMACK fn=smack_file_open action=denied subject="User" object="System::Privileged" requested=r pid=2765 comm="tlm-sessiond" path="/opt/var/log/wtmp" dev="mmcblk0p3" ino=822

A tlm-sessiond only create the shell process in /etc/passwd directly, and this shell process does nothing.
So, changing tlm's smack from "User" to "System" does not change user systemd and its associated processes.
===========================================================================================================================
sh-3.2# pstree -p | grep tlm
           |-tlm(551)-+-tlm-sessiond(567)-+-bash(622)
           |          |                   |-{tlm-sessiond}(569)
           |          |                   `-{tlm-sessiond}(572)
           |          |-{tlm}(565)
           |          `-{tlm}(566)

sh-3.2# ps -auxZ | grep tlm
User                            root       551  0.0  0.2  25912  2672 ?        Ssl  11:23   0:00 /usr/bin/tlm
User                            root       567  0.0  0.3  26848  3104 ?        Sl   11:23   0:00 /usr/bin/tlm-sessiond

sh-3.2# ps -auxZ | grep 622
User                            owner      622  0.0  0.1   4628  1068 tty7     Ss+  11:23   0:00 /bin/bash  <== shell process

Change-Id: I7376be55ea57ab187a79ab99721e05e1d8ea38a1
Signed-off-by: Hyotaek Shim <hyotaek.shim@samsung.com>