mountinfo.Mounted: incorrect results for some corner cases

[kolyshkin]

As reported by @mkimuram here: kubernetes/kubernetes#105833 (comment)

Obviously, issues a and b can be fixed by using filepath.EvalSymlinks (and in view of that part of #86 might need to be reverted).

Not sure what to do with issue c for now...

[mkimuram]

Not sure what to do with issue c for now...

Actually, issue c should be also fixed if we are sure that the path is no longer a symlink (In that case, /foo, instead of /baz/bar/mounted, is passed as an argument).

[kolyshkin]

@mkimuram right :) somehow I missed it yesterday.

I am adding more test cases, as well as fixes.

[thaJeztah]

I was looking if we should do a new release of the modules in this repository; let me wait until this one is addressed 👍 (from your comment, I gather you're working on this, @kolyshkin ?)

[kolyshkin]

@thaJeztah yes, I want to release mountinfo 0.5.0 once all this is merged. PTAL #89, #90.