Modify n-acd library to use ebpf whenever it is possible.
This is done by always making a `sys_call` for bpf resources. If this
call fails program continues to run normally the only difference is that
ebpf is not used.

Edit the test for bpf map to only run when bpf map is successfully
created.

Fixes: 7ee0da3eaffd ('build: don't "update-po" during make dist')

https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/merge_requests/1441

libnm-core-impl has lots of internal meta data about the properties.
In particular, which properties exist (their names), and their D-Bus
type.

We should use this information for our manual pages. For example,
currently `man nm-settings-dbus` has nonsense like: "Value Type: array
of string", when it should be reall "as".

In a first step, generate an XML with that meta data for later use.

This is the better name, becuse this is not in particular about "docs".
It's about generating an XML with the information from the settings
meta data for nmcli.

We will do something similar with the libnm-core meta data.

It just feels nicer to be explicit about the filenames and
not rely on a specific naming.

Also, in meson we can directly pass the target as argument, which
expands to the filename but also adds a dependency.

Fixes: ab8fdb73e6be ('build: commit pre-generated "generate-docs-nm-settings-nmcli.xml" to git')

<assert.h> only defines __assert_fail() if NDEBUG is not on.
Fix that.

Fixes: 8e3299498dd1 ('std-aux,glib-aux: rework nm_assert() implementations')

https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/merge_requests/1442

Add a comment. Also, restructure the check so that it is (hopefully)
easier to read.