Since check_packet is using network channels (file descriptors), it is
better declared as a network operations.  This allows, for example,
to make a simulator using ARCH=unix and only changing TIME= .
Signed-off-by: Alessandro Rubini <rubini@gnudd.com>

This changes all "Name Surname for CERN" to "Copyright CERN, author
Name Surname".  This is trivial and makes no change, with a few
expections:

- all trivial Makefiles that had "for CERN" lines have now no
attributions, as they are trivial anyways.

- a few unrepresented files have not the copyright notice (especially
ptpdump, that I wrote in 2012).

- a few "for CERN" remain in subprojects, where I didn't touch anyrhing
Signed-off-by: Alessandro Rubini <rubini@gnudd.com>

The unix time and network operations are going to be used as a fall-back
solution by other timing engines.

For example, hardware-specific timestamping capabilities can be
selected (such as the Linux ioctl API) but if the Ethernet interface
(and thus the pp_instance) doesn't support the feature, related code
will be able to set back the unix operations in place.
Signed-off-by: Alessandro Rubini <rubini@gnudd.com>

The contents of this directory are pretty portable anyways, and
the internal files were actually called "posix-io.c" and so on.
So let's get rid of the too-politica "gnu-linux" naming and of
the too-little-political "posix" at the same time.  We build
on Unix roots, so let's call our architecture like that.
Signed-off-by: Alessandro Rubini <rubini@gnudd.com>
Acked-by: Aurelio Colosimo <aurelio@aureliocolosimo.it>