Removing libseccomp installations and disabling CGO

[amitschendel]

[Title: Remove libseccomp and CGO usage]

Removed all installations of the package from the code.

How to use

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Testing done

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[eiffel-fl]

Hi.

An external contribution which removes an action in your CI: I say YES!
I have some comments but they are minor ones, I will run the CI to see if everything builds correctly.

Best regards.

[eiffel-fl]

Everything is OK from the CI point of view and the code addresses the problem well! Thank you!

Can you please squash your 3 commits in one, as they share the same semantic?

[mauriciovasquezbernal]

One minor nit. Already LGTM.

@eiffel-fl now that we don't have CGO anymore, are these libraries still needed?

inspektor-gadget/Dockerfiles/gadget-default.Dockerfile

Lines 22 to 38 in 2ecc9fa

	# We need a cross compiler and libraries for TARGETARCH due to CGO.
	RUN set -ex; \
	export DEBIAN_FRONTEND=noninteractive; \
	dpkg --add-architecture ${TARGETARCH} && \
	apt-get update && \
	apt-get install -y gcc make ca-certificates git libelf-dev:${TARGETARCH} \
	pkg-config:${TARGETARCH} && \
	if [ "${TARGETARCH}" != "${BUILDARCH}" ]; then \
	if [ ${TARGETARCH} = 'arm64' ]; then \
	apt-get install -y gcc-aarch64-linux-gnu; \
	elif [ ${TARGETARCH} = 'amd64' ]; then \
	apt-get install -y gcc-x86-64-linux-gnu; \
	else \
	>&2 echo "${TARGETARCH} is not supported"; \
	exit 1; \
	fi \
	fi

[mauriciovasquezbernal]

Suggested change

	- `pkg-config` helper
	- `pkg-config`

[eiffel-fl]

The above contains "gcc compiler", so I guess having "pkg-config helper" is OK.
Otherwise, we can just remove both "compiler" and "helper".

[eiffel-fl]

@eiffel-fl now that we don't have CGO anymore, are these libraries still needed?

We should not need them, particularly as removing libelf-dev was already done here:
eb9b769

I will focus on libelf-dev and pkgconfig in a followup PR, let's focus on libseccomp in the present.

[eiffel-fl]

Merging as if we remove pkg-config I will deal with the documentation too.
Thank you for this contribution! Appreciated!