Allow save / load from other game modules

[TobiasKarnat]

Using other game modules like from Yamagi Quake II for e.g. the expansion modules work fine, but save / load is disabled.

This patch enables save (even autosave on map start) / load again. I did not experience any problems.

--- a/src/server/save.c	2021-09-29 10:09:30.000000000 +0200
+++ b/src/server/save.c	2021-10-01 13:19:24.961544602 +0200
@@ -381,8 +381,8 @@
     SV_InitGame(MVD_SPAWN_DISABLED);
 
     // error out immediately if game doesn't support safe savegames
-    if (!(g_features->integer & GMF_ENHANCED_SAVEGAMES))
-        Com_Error(ERR_DROP, "Game does not support enhanced savegames");
+/*    if (!(g_features->integer & GMF_ENHANCED_SAVEGAMES))
+        Com_Error(ERR_DROP, "Game does not support enhanced savegames");*/
 
     // read game state
     len = Q_snprintf(name, MAX_OSPATH,
@@ -462,8 +462,8 @@
 	if (dedicated->integer && !Cvar_VariableInteger("coop"))
         return 1;
 
-    if (!(g_features->integer & GMF_ENHANCED_SAVEGAMES))
-        return 1;
+/*    if (!(g_features->integer & GMF_ENHANCED_SAVEGAMES))
+        return 1;*/
 
     if (Cvar_VariableInteger("deathmatch"))
         return 1;
@@ -642,10 +642,10 @@
     }
 
     // don't bother saving if we can't read them back!
-    if (!(g_features->integer & GMF_ENHANCED_SAVEGAMES)) {
+/*    if (!(g_features->integer & GMF_ENHANCED_SAVEGAMES)) {
         Com_Printf("Game does not support enhanced savegames.\n");
         return;
-    }
+    }*/
 
     if (Cvar_VariableInteger("deathmatch")) {
         Com_Printf("Can't savegame in a deathmatch.\n");