[DX010] Remove executable permission of fancontrol.service for dx010

[bingwang-ms]

- Why I did it
Systemd keeps reporting WARNING in syslog

 WARNING systemd[1]: Configuration file /lib/systemd/system/fancontrol.service is marked executable. Please remove executable permission bits. Proceeding anyway.

This PR is to remove executable permission of fancontrol.service for dx010 platform.
- How I did it
Remove executable permission of /lib/systemd/system/fancontrol.service for dx010 platform.
- How to verify it
Verified on DX010, and confirm that the fancontrol service is running, and the WARNING log is no longer found in syslog.

admin@str-dx010-acs-4:~$ systemctl status fancontrol
● fancontrol.service - fan speed regulator
   Loaded: loaded (/lib/systemd/system/fancontrol.service; enabled; vendor preset: enabled)
   Active: active (running) since Mon 2020-10-12 02:33:26 UTC; 20min ago
 Main PID: 1303 (fancontrol.sh)
    Tasks: 3 (limit: 4671)
   Memory: 5.4M
   CGroup: /system.slice/fancontrol.service
           ├─1303 /bin/sh /etc/init.d/fancontrol.sh start
           ├─2460 /bin/bash /usr/local/bin/fancontrol /usr/share/sonic/device/x86_64-cel_seastone-r0/fancontrol-F2B
           └─4848 sleep 2

- Which release branch to backport (provide reason below if selected)

• 201811
• 201911
• 202006

- Description for the changelog

Remove executable permission of fancontrol.service for dx010

- A picture of a cute animal (not mandatory but encouraged)