(decl): Remove broken and redundant check of declarer's country

number.  Check is redundant, because invalid values can come only from
natarg(), and those are checked above.  Check is broken because
natarg() returns negative value on error, not 255.

src/lib/commands/decl.c

@@ -101,8 +101,6 @@ decl(void)
 	if (who < 0)
 	    return RET_SYN;
     }
-    if (who == 255)
-	return RET_SYN;
 
     natp = getnatp(who);
     while (nxtitem(&ni, (s_char *)&nat)) {