Revert removing iiod interpreter calls

[dNechita]

'readfd_io' and 'writefd_io' are used when building with cmake flag WITH_AIO=OFF. They are used here:

libiio/iiod/interpreter.c

Lines 165 to 166 in 73bba25

	pdata.readfd = readfd_io;
	pdata.writefd = writefd_io;

This reverts commit a80a312.

PR Description

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PR Type

• Bug fix (a change that fixes an issue)
• New feature (a change that adds new functionality)
• Breaking change (a change that affects other repos or cause CIs to fail)

PR Checklist

• I have conducted a self-review of my own code changes
• I have commented new code, particulary complex or unclear areas
• I have checked that I did not intoduced new warnings or errors (CI output)
• I have checked that components that use libiio did not get broken
• I have updated the documentation accordingly (GitHub Pages, READMEs, etc)

[dNechita]

@AlexandraTrifan thank you for finding this issue.

[rgetz]

This just says there is are missing gaps in CI - we should be building with a variety of build settings to make sure this works. (look at build_readme, and decide which ones should be toggled, and only build on one system).

[dNechita]

This just says there is are missing gaps in CI - we should be building with a variety of build settings to make sure this works. (look at build_readme, and decide which ones should be toggled, and only build on one system).

Yes, I was thinking the same thing. I even though automatically generating all cmake flags combinations and do a build for each combination, but not all combination is valid. Deciding a list of combination that make sense should be a good improvement.