tools: ynl: add distclean to .PHONY in all makefiles

Donald points out most YNL makefiles are missing distclean
in .PHONY, even tho generated/Makefile does list it.

Suggested-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

tools: ynl: rename make hardclean -> distclean

The make target to remove all generated files used to be called
"hardclean" because it deleted files which were tracked by git.
We no longer track generated user space files, so use the more
common "distclean" name.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

tools: ynl: order building samples after generated code

Parallel builds of ynl:

make -C tools/net/ynl/ -j 4

don't work correctly right now. samples get handled before
generated, so build of samples does not notice that protos.a
has changed. Order samples to be last.

Link: https://lore.kernel.org/r/20231129193622.2912353-4-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

tools: ynl: don't regen on every make

As far as I can tell the normal Makefile dependency tracking
works, generated files get re-generated if the YAML was updated.
Let make do its job, don't force the re-generation.
make hardclean can be used to force regeneration.

Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20231003153416.2479808-3-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

ynl: regenerate all headers

Also add support to pass topdir to ynl-regen.sh (Jakub) and call
it from the makefile to update the UAPI headers.

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Co-developed-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Link: https://lore.kernel.org/r/20230727163001.3952878-4-sdf@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

tools: ynl: user space helpers

Add "fixed" part of the user space Netlink Spec-based library.
This will get linked with the protocol implementations to form
a full API.

Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>