setupapi: Make sure machine name is non-empty before failing.
[wine] / programs / ipconfig /
drwxr-xr-x   ..
-rw-r--r-- 214 Makefile.in
-rw-r--r-- 12394 ipconfig.c
-rw-r--r-- 1594 ipconfig.h
-rw-r--r-- 1684 ipconfig.rc