use llvm-strip and llvm-ar if the arch-specific-named strip and ar are not present

[codyps]

Should fix #38

[bbqsrc]

Thanks for the contribution. I wonder if we should now also check if the new path exists as well, and if neither do, return an error?

[codyps]

We could, however:

• for ar: making it a hard error here (where we're choosing to define some env vars), might take something that wouldn't be an issue (say, if the build happens to not require ar for some reason) and turn it into a hard error, leading folks to need to write workarounds (like creating a fake ar, or making some symlinks)
• for strip: it seems like we could do this. Though I believe trying to run the command would provide us with a descriptive error (one we need to handle well anyhow)

[bbqsrc]

If someone doesn't need ar, cargo-ndk incidentally working isn't ideal, since it's not going to be a valid NDK in any case if it can't find all the basic pieces from the NDK. I prefer things to break when the environment is proven to not be coherent than accidentally work, had that happen to me enough times to become deeply sad. 😄

[harryfei]

Why this closed? We need this PR to work with the new version NDK.

[bbqsrc]

This is closed for the reasons clearly stated in my previous comment. If someone wants to make a PR that achieves the goals of this PR without causing the issues it causes, it will be merged.