Fix overlaying bpf mount

[nocturo]

The check in the initContainer for the deployed daemonSet is only looking for exact text from the mount command, which leads to false positives and bpfman-operator mounting an overlay bpf filesystem causing problems with other applications relying on it. (I had issues with Cilium but it will break anything that is using it)

Below is an excerpt of what I mean, first we check the initial state using current method:

root@test:/# /bin/mount | /bin/grep 'bpffs on /sys/fs/bpf'
root@test:/# echo $?
1
root@test:/# ls /sys/fs/bpf/
cilium  tc
root@test:/# mount|grep bpf
bpf on /sys/fs/bpf type bpf (rw,nosuid,nodev,noexec,relatime,mode=700)
root@test:/#

then after bpfman-operator has been deployed:

root@test:/# mount|grep bpf
bpf on /sys/fs/bpf type bpf (rw,nosuid,nodev,noexec,relatime,mode=700)
bpffs on /sys/fs/bpf type bpf (rw,relatime)

This PR addresses the problem by using findmnt for finding the right mount type for /sys/fs/bpf mountpoint. After changing my daemonSet to this, I no longer have issues running bpfman-operator and Cilium.

[frobware]

LGTM, but would prefer long form options to findmnt.

[frobware]

Suggested change

	if ! /usr/bin/findmnt -n -t bpf /sys/fs/bpf >/dev/null 2>&1; then
	if ! /usr/bin/findmnt --noheadings --types bpf /sys/fs/bpf >/dev/null 2>&1; then

I'd prefer long-form flags instead of short flags for self-documentation. I had to go lookup -n to see what that did.

[nocturo]

Not a problem, pushed new commit with long-form flags.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 0.00%. Comparing base (f418fd7) to head (22f0229).
⚠️ Report is 26 commits behind head on main.

Additional details and impacted files

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[frobware]

@nocturo - Just a quick heads-up and courtesy call: I’ve raised #490. I wanted to mention this since you previously raised and fixed the bpffs mount issue. The goal of #490 is to create a Go implementation that performs the equivalent functions of findmnt/mount. This means we can eliminate the need for an init container that requires a Fedora image, as the functionality will now be integrated into the agent. From your perspective, nothing should change...