utils/main.c: Call to function with fewer arguments than declared parameters

Copilot Autofix rejected: DBFileRecovery(MainFileName);

database/DBio.c looks to take NULL as a value for automatic recovery.

Related commits:
commit 231a299b16 (tag: 8.2.0)
Date:   Tue Apr 25 08:41:48 2017 -0400
    Initial commit at Tue Apr 25 08:41:48 EDT 2017 by tim on stravinsky

utils/main.c

@@ -1164,7 +1164,7 @@ mainInitFinal()
 
     if (mainRecover && MakeMainWindow)
     {
-	DBFileRecovery();
+	DBFileRecovery(NULL); /* automatic search most recent */
     }
 
     /*