whitelist a new warning in cmd.c

src/cmd.c(1253): warning: conditional expression is constant

src/cmd.c

@@ -1221,6 +1221,8 @@ wiz_level_change(void)
     return ECMD_OK;
 }
 
+DISABLE_WARNING_CONDEXPR_IS_CONSTANT
+
 /* #wiztelekinesis */
 static int
 wiz_telekinesis(void)
@@ -1254,6 +1256,8 @@ wiz_telekinesis(void)
     return ECMD_OK;
 }
 
+RESTORE_WARNING_CONDEXPR_IS_CONSTANT
+
 /* #panic command - test program's panic handling */
 static int
 wiz_panic(void)