[Fwutil] Add missing new line to version prints

[aalamsi22]

Description

fw_util version prints were missing a new line at the end. See the log below to explain

Pre fw_util new-line fix

[ ~]# fw_util --config_file=/opt/fboss/share/platform_configs/fw_util.json --fw_target_name=fan_cpld0 --fw_action=version
I0205 03:51:04.610634  3325 PlatformNameLib.cpp:73] Platform name read from cache: MERU800BFA
I0205 03:51:04.610693  3325 ConfigLib.cpp:33] Using config file: /opt/fboss/share/platform_configs/fw_util.json
fan_cpld0 : 1.2[ ~]# 
[ ~]# 

After

[ ~]# fw_util --config_file=/opt/fboss/share/platform_configs/fw_util.json --fw_target_name=fan_cpld0 --fw_action=version
I0205 03:51:04.610634  3325 PlatformNameLib.cpp:73] Platform name read from cache: MERU800BFA
I0205 03:51:04.610693  3325 ConfigLib.cpp:33] Using config file: /opt/fboss/share/platform_configs/fw_util.json
fan_cpld0 : 1.2
[ ~]# 
[ ~]#