cleanup(libsinsp): remove CYGWING_AGENT feature gate

[therealbobo]

What type of PR is this?

Uncomment one (or more) /kind <> lines:

/kind bug

/kind cleanup

/kind design

/kind documentation

/kind failing-test

/kind feature

Any specific area of the project related to this PR?

Uncomment one (or more) /area <> lines:

/area API-version

/area build

/area CI

/area driver-kmod

/area driver-bpf

/area driver-modern-bpf

/area libscap-engine-bpf

/area libscap-engine-gvisor

/area libscap-engine-kmod

/area libscap-engine-modern-bpf

/area libscap-engine-nodriver

/area libscap-engine-noop

/area libscap-engine-source-plugin

/area libscap-engine-savefile

/area libscap

/area libpman

/area libsinsp

/area tests

/area proposals

Does this PR require a change in the driver versions?

/version driver-API-version-major

/version driver-API-version-minor

/version driver-API-version-patch

/version driver-SCHEMA-version-major

/version driver-SCHEMA-version-minor

/version driver-SCHEMA-version-patch

What this PR does / why we need it:

This removes an unused define.

Which issue(s) this PR fixes:

Fixes #

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

NONE

[github-actions]

Please double check driver/SCHEMA_VERSION file. See versioning.

/hold

[FedeDP]

/milestone 0.15.0

[FedeDP]

/unhold no schema bump needed.

[FedeDP]

/approve

[poiana]

LGTM label has been added.

Git tree hash: cf4e0d64c289312069b6e9f7bbbca14ec8e15cde

[jasondellaluce]

/approve

[poiana]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: FedeDP, jasondellaluce, therealbobo

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• OWNERS [FedeDP,jasondellaluce]

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[FedeDP]

/unhold