configure: add a mechanism to check if a header can be used

[mobin-2008]

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Your background I'm currently a maintainer and I want to improve user experience with configure script.

The problem Currently configure just disables linux/ioprio.h header usage because it may not be available. I think this is not very nice to be default and can be improved.

The solution I want to add check_header() function to configure to be used in this case, which does:

1. Create a file with requested header
2. Compile it to see if it compiles
3. returns success otherwise failure based on compiler result

Additional context

[davmac314]

Sounds ok in principle.

[mobin-2008]

"Fixes #issue" in the PR description was supposed to close this issue. Anyway, fixed by https://github.com/davmac314/dinit/commit/1c88395c9ecb343531ff7f01e5394084822f4d2d

[davmac314]

"Fixes #issue" in the PR description was supposed to close this issue

I disabled that functionality as it can result in incorrectly closed issues.