Fixes the following memory leaks that occur when initial map loading or socket opening fails:
```
[2021-12-28 12:00:36][server]: starting...
[2021-12-28 12:00:36][mapchecker]: invalid standard map
[2021-12-28 12:00:36][server]: failed to load map. mapname='dm1'
=================================================================
==61193==ERROR: LeakSanitizer: detected memory leaks
Direct leak of 8 byte(s) in 1 object(s) allocated from:
#0 0x7f6c17188947 in operator new(unsigned...
1
