desc.c: do not use xmalloc, use umove_or_printaddr and printaddr

* desc.c (printflock64, printflock): Use umove_or_printaddr.
(decode_select): Do not use xmalloc.  Use umoven_or_printaddr
and printaddr.
(sys_oldselect): Use printaddr.
(sys_epoll_ctl): Use umoven_or_printaddr and printaddr.
(print_epoll_event_array): New function.
(sys_epoll_wait_common): Use it.
(sys_pselect6): Use umove_or_printaddr.
(sys_eventfd2): Use printaddr.
1 file changed