Fix for #2210 (SHOW TABLE STATUS fails when .frm is corrupted)

We signed error instead of returning the result


sql/sql_show.cc:
  we need this assignement in libmysqld to not to issue error

sql/sql_show.cc

@@ -520,6 +520,7 @@ int mysqld_extend_show_tables(THD *thd,const char *db,const char *wild)
       // Send error to Comment field
       protocol->store(thd->net.last_error, system_charset_info);
       thd->net.last_error[0]=0;
+      thd->net.last_errno= 0;
     }
     else
     {