Fix for issue 1517 'DOI Setup Broken'

When attempting to install Day of Infamy it will fail with the following:

Creating log directories
=================================
installing log dir: /home/doiserver/log...OK
installing LinuxGSM log dir: ...mkdir: cannot create directory '': No such file or directory
FAIL

---

The 'lgsmlogdir' variable is missing in doiserver.

linuxgsm.sh

@@ -29,6 +29,7 @@ servicename="${selfname}"
 lockselfname=".${servicename}.lock"
 lgsmdir="${rootdir}/lgsm"
 logdir="${rootdir}/log"
+lgsmlogdir="${logdir}/lgsm"
 steamcmddir="${rootdir}/steamcmd"
 serverfiles="${rootdir}/serverfiles"
 functionsdir="${lgsmdir}/functions"