Add support to ppc64le with gcc. Install gettext

[gururajrkatti]

Add support to Linux on Power Little Endian architecture. Continuously building/testing on this platform along with intel will help in detecting/fixing the problems in early stage.

[ars3niy]

We seem to replacing travis with github actions though :-|

[BenWiederhake]

Good news everyone, GitHub Actions doesn't support running natively on other architectures. However, it does support running stuff in Docker: https://github.com/marketplace/actions/run-on-architecture#advanced-example

So one way to do this on GA is by creating a new workflow which basically just runs all build steps inside docker. Since we don't use any advanced stuff, this should be a copy-and paste job, since the cache action can run outside of docker. Also, this means we can in theory extend to aarch64, armv7, and s390x, just by extending the matrix.

[gururajrkatti]

@ars3niy thanks for the feedback. Travis does want to continue open source support Pl. refer to https://blog.travis-ci.com/oss-announcement if that is the concern. Meanwhile I can check if it is possible to run these steps as part of a docker,

[BenWiederhake]

The announcement conveniently omits all the crucial parts:

• You get automatically "upgraded" to a free plan.
• The free plan only gives you "10K free credit allotment!!!" which is 1000 build minutes, or roughly 8-11 tdlib-builds. Note that your build matrix extension consumes even more minutes per build, so 1000 minutes only last 5-8 builds.
• If that's not enough, we would have to politely kindly ask and beg for mercy, every single time, and Travis has apparently put that on hold for a while – the "on hold" part is probably over by now, but why trust them now? Sure they approve requests for OpenSSL and Apache, because it looks good. I doubt they will do the same for tdlib-purple.
• Also, who is going to write that "begging for mercy" e-mail every few weeks?
• Travis was bought up by a well-known vulture capitalist company and fired most of it's senior staff – I'm surprised it took so long to see the first results.
• Even Wikipedia and other projects think that Travis is not a good idea anymore.
• The 10K credits are per user, not per project. So if ars3niy has the "AUDACITY!!!!" to be a coder, and, y'know, code stuff, and have other projects, then this also counts against the 10K credit allotment. Yes, this is a "free plan", much in the same way you can get a free "meal" at a restaurant that only consists of a glass of water. (I'm not mad at Travis for charging money btw. They have to pay electricity and rent and wages etc, so charging large customers makes perfect sense. However, I would not accept that deal for free software.)
• The 10K allotment refreshes every month, I mean never, except when it does, but it doesn't. These users are confused about this, too. The Travis Plan overview provides clarity by saying "Error: No repositories found for organization". I guess they don't know either. My personal overview says "8950 available credits (purchase date: December 30, 2020)", and doesn't indicate either direction, but "purchase" doesn't sound like it's going to be free.

[ars3niy]

I'm a simple person. Ben say github actions, me merge. Now can't merge this one :(

[BenWiederhake]

Since gururajrkatti already wrote this commit twice, I'll have a look at how to write it for Github Actions – I will do that next year, though. Guten Rutsch, as we say in Germany! :)