Add socat package

[koooosh]

Issue number: #4055

Closes #4055

Description of changes:

This change adds the socat package to the aws-dev variant to be used by our downstream customers. Specifically, it includes the following:

• socat.spec which is similar to the previous spec file we had for socat with some changes to account for new features added to the updated version 1.8.0.0
• Cargo.toml for the new package
• 0001-xioopts-conditionally-compile-applyopts_termios_valu.patch needed to successfully compile the new socat version. Prior to this patch, we got a compilation error for an undefined reference to xiotermios_value, which was defined in a conditionally compiled code block that we want disabled. To fix this, in the patch we add that same conditional compilation directive WITH_TERMIOS to the function applyopts_termios_value which was using that undefined reference.
• Adding socat as a dependency to aws-dev which includes updates to its Cargo.toml and the general variant Cargo.lock

Testing done:

aws-dev variant successfully builds and launches. socat binary exists and runs successfully. We tested socat by using it to connect a TCP port to a UNIX socket and verifying we can use the port to get responses.

Further testing for the downstream use case also looks good.

Terms of contribution:

By submitting this pull request, I agree that this contribution is dual-licensed under the terms of both the Apache License, version 2.0, and the MIT license.

[bcressey]

Convention is not to indent the lines guarded by #ifdef - that keeps the code readable in the case where it's used, and for the purposes of this patch will minimize the delta.

[koooosh]

Got it, will remove those indents