Move to upstream Sddl/SecurityAttribute functions

[zx2c4]

These have been moved into x/sys/windows entirely.

[msftclas]

All CLA requirements met.

[jterry75]

@zx2c4 - The change looks good but I am worried about just deleting the exported functions. I think that we should likely go through a deprecation period. @kevpar / @jstarks Thoughts?

[jstarks]

We should leave the existing functions but have them call through to the windows package (and only if the semantics are exactly the same).

[thaJeztah]

Heads up: from the discussion on moby/moby#40021 (comment)

LGTM, but I'd wait for the outcome of the discussion on golang/go#34610 where the decision might be to revert the change to SecurityAttributes and introduce a new struct type with a different name.

So it might be good to hold off on this one

[katiewasnothere]

Is there any update on this?

[thaJeztah]

My comment above is now outdated; it was decided not to revert (moby/moby#40021 (comment))

This is good to go now that golang/go#34610 has been closed and it was decided there will be no revert (golang/go#34610 (comment))

So from that perspective this should be good to go (I'm not a maintainer here though!)

[katiewasnothere]

@jstarks do we want these changes?

We need to update (for example) hcsshim to no longer use out of date functions such as SddlToSecurityDescriptor so we can update the x/sys dependency there. Might be good then to update this here for consistency.

[kolyshkin]

We need to update (for example) hcsshim to no longer use out of date functions such as SddlToSecurityDescriptor so we can update the x/sys dependency there. Might be good then to update this here for consistency.

It was a simple fix, unless I'm missing something; please see the second commit in microsoft/hcsshim#828

[katiewasnothere]

I've made a new PR #172 to address a few other things.