[LTP] [PATCH] travis: Add centos7 build

[Petr Vorel]

Hi Xu,

> > > I have this idea when I meet ALG_SET_AEAD_ASSOCLEN undefined error on centos7.
> > > Add centos7 travis target, it is more friendly for centos7 user and it is more
> > > meaningful than centos6.

> > OK, how about replacing CentOS 6 with CentOS 7?
> I have no objection about this because my kernel test team only uses
> centos7/8 to test and doesn't use centos6 for a long time.
OK. I don't have either, although I hesitated to sent this patch.

> But I think ltp community should reach a consensus that minimal
> glibc/kernel/gcc(clang) version , so we can drop the corresponding code in
> travis or m4.

> Also, we can raise "Define minimal supported kernel and (g)libc version"
> topic again.
Well, last time I remember we decide to drop CentOS 6 after the release. But I
haven't done it. I also planned to create wiki pagge "Supported kernel and
libc", but haven't done it. Feel free to send a patch for any of these two.
But I'd prefer to do the replacement (7 instead of 6) instead of adding it,
because travis already run for quite long.

Kind regards,
Petr