[LTP] [PATCH v1] Revert "m4: Remove check for io_set_eventfd"

[Petr Vorel]

Hi Edward,

> This reverts commit 5ca0d16d66c42fbfa483c180de4c881de7f182cc.

> Android has libaio headers but is missing some functions including
> io_set_eventfd.  Without these checks it will fail to compile.

Ack to revert as I guess we cannot avoid this. But we should fix newly
introduced warnings on 2.71:

configure.ac:391: warning: The macro `AC_TRY_LINK' is obsolete.
configure.ac:391: You should run autoupdate.
./lib/autoconf/general.m4:2920: AC_TRY_LINK is expanded from...
m4/ltp-eventfd.m4:6: LTP_CHECK_SYSCALL_EVENTFD is expanded from...
configure.ac:391: the top level

-AC_TRY_LINK([
+AC_LINK_IFELSE([AC_LANG_PROGRAM([[

...

-],
+]],

NOTE: if you don't have 2.71 available I can fix this myself.

...
> +++ b/testcases/kernel/syscalls/eventfd/eventfd01.c
> @@ -1,6 +1,5 @@
>  /*
>   *   Copyright (c) 2008 Vijay Kumar B. <vijaykumar@bravegnu.org>
> - *   Copyright (c) Linux Test Project, 2008-2022
NOTE for person who merges this: this copyright should be kept (amend the commit
before merge).

Kind regards,
Petr