Currently "src/" mostly contains the source code of the daemon.
I say mostly, because that is not true, there are also the device,
settings, wwan, ppp plugins, the initrd generator, the pppd and dhcp
helper, and probably more.

Also we have source code under libnm-core/, libnm/, clients/, and
shared/ directories. That is all confusing.

We should have one "src" directory, that contains subdirectories. Those
subdirectories should contain individual parts (libraries or
applications), that possibly have dependencies on other subdirectories.
There should be a flat hierarchy of directories under src/, which
contains individual modules.

As the name "src/" is already taken, that prevents any sensible
restructuring of the code.

As a first step, move "src/" to "src/core/". This gives space to
reorganize the code better by moving individual components into "src/".

For inspiration, look at systemd's "src/" directory.

https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/merge_requests/743

We have many static helper libraries, like libnm-glib-aux or libnm-core.
These can be statically linked in any end-binary as internal API. However, they
must only be linked once.

Also, we have various plugins (device, settings, ppp, wwan) which are
dlopened by NetworkManager. They should use the symbols from
NetworkManager core. It is important that they do not link with the
static libraries already, because also NetworkManager core links with
it, so these symbols will be duplicate.

As the symbols are internal, you might think that it is not a real
problem to duplicate them. However, there are also global variables,
like the hash tables for NMRefStr or the seed for NMHash. These global
variables must be only be used once, and hence also these symbols must
no be duplicated.

Fix that by adding a new dependency that is for the core plugins. This
dependency only has "include_directories" but not "link_with".

Naming for us is hard, because everything is an "nm". However, let's
standardize on the term "core" for the daemon, and not "daemon".

Eventually I would like to move the daemon from "src/" to "src/core/",
rename the dep in anticipation of that.

We want to use this by "shared/nm-platform", which should have
no dependency on "libnm-core".

Move "libnm-core/nm-ethtool-utils.h" to "libnm/nm-ethtool-utils.h" so
that it is only used by libnm. This file contains the defines for
the option names.

Also, symlink "libnm/nm-ethtool-utils.h" as "shared/nm-base/nm-ethtool-utils-base.h".
We want to use the same defines also internally. Since they are both
public API (must be in libnm) and should be in "shared/nm-base", this
is the way.

We want to use these defines for option names also in "shared/nm-base"
(and in turn in "shared/nm-platform), which cannot include "libnm-core".

However, they are also public API of libnm.

To get this done, in a first step, move these defines to a new header
"libnm-core/nm-ethtool-utils.h".

Since now the name "nm-ethtool-utils.h" is taken, also rename
nm-libnm-core-intern files.

These SPDX license identifiers are deprecated ([1]). Update them.

[1] https://spdx.org/licenses/

  sed \
     -e '1 s%^/\* SPDX-License-Identifier: \(GPL-2.0\|LGPL-2.1\)+ \*/$%/* SPDX-License-Identifier: \1-or-later */%' \
     -e '1,2 s%^\(--\|#\|//\) SPDX-License-Identifier: \(GPL-2.0\|LGPL-2.1\)+$%\1 SPDX-License-Identifier: \2-or-later%' \
     -i \
     $(git grep -l SPDX-License-Identifier -- \
         ':(exclude)shared/c-*/' \
         ':(exclude)shared/n-*/' \
         ':(exclude)shared/systemd/src' \
         ':(exclude)src/systemd/src')

https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/merge_requests/709

Add a new key management option to support WPA3 Enteprise wifi
connection.

Only supported with wpa_supplicant for the time being.

Signed-off-by: Antonio Cardace <acardace@redhat.com>