netapi32: Don't bother to clean up at process exit.

dlls/netapi32/netapi32.c

@@ -33,17 +33,14 @@ BOOL WINAPI DllMain (HINSTANCE hinstDLL, DWORD fdwReason, LPVOID lpvReserved)
 
     switch (fdwReason) {
         case DLL_PROCESS_ATTACH:
-        {
             DisableThreadLibraryCalls(hinstDLL);
             NetBIOSInit();
             NetBTInit();
             break;
-        }
         case DLL_PROCESS_DETACH:
-        {
+            if (lpvReserved) break;
             NetBIOSShutdown();
             break;
-        }
     }
 
     return TRUE;