check: verify ino and dev of overlayfs files in /proc/pid/maps

[avagin]

Check that the file device and inode shown in /proc/pid/maps match values returned by stat(2).

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 62.50000% with 42 lines in your changes are missing coverage. Please review.

Project coverage is 70.20%. Comparing base (cb39c62) to head (4bf16da).

:exclamation: Current head 4bf16da differs from pull request most recent head 8e83b7a. Consider uploading reports for the commit 8e83b7a to get more accurate results

Files	Patch %	Lines
criu/cr-check.c	62.50%	42 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## criu-dev #2320 +/- ## ============================================ - Coverage 70.21% 70.20% -0.01% ============================================ Files 132 132 Lines 34372 34484 +112 ============================================ + Hits 24134 24210 +76 - Misses 10238 10274 +36 ```

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[Snorch]

Looks good.

minor nits:

• note "clang-format: Possible coding style problem" warnings, alignment may be improved
• error messages like pr_perror("syscallname"); may be rewritten in "Unable to syscallname smth." style

Do we want to add it to kdat?

[github-actions[bot]]

A friendly reminder that this PR had no activity for 30 days.