'RELENG_7_0_0_RELEASE'.

This commit was manufactured to restore the state of the 7.0-RELEASE image.

Implement new apply callback mechanism to handle item forwarding.
When item forwarded, refence counter is incremented, when item
processed, counter decremented. When counter reaches zero,
apply handler is getting called.
It allows to report connect() call status only when it is really completed.

Reviewed by:	julian
Approved by:	re (kensmith)

protocol entry points using functions named proto_getsockaddr and
proto_getpeeraddr rather than proto_setsockaddr and proto_setpeeraddr.
While it's true that sockaddrs are allocated and set, the net effect is
to retrieve (get) the socket address or peer address from a socket, not
set it, so align names to that intent.

specific privilege names to a broad range of privileges.  These may
require some future tweaking.

Sponsored by:           nCircle Network Security, Inc.
Obtained from:          TrustedBSD Project
Discussed on:           arch@
Reviewed (at least in part) by: mlaier, jmg, pjd, bde, ceri,
                        Alex Lyashkov <umka at sevcity dot net>,
                        Skip Ford <skip dot ford at verizon dot net>,
                        Antoine Brodin <antoine dot brodin at laposte dot net>

Reported by:	Coverity
CID:		1556

  - Inline ship_msg() into ngs_rcvmsg().
  - Plug memory leak in case if no control socket present.
  - Remove malloc() and allocate the sockaddr on stack.
  - style(9).

  - Use malloc() and free() instead of MALLOC() and FREE() macros.
  - Do not check malloc results if M_WAITOK was used.
  - Remove linked list of all netgraph sockets. It isn't needed.
  - Use ng_findhook() instead of searching the list ourselves.
  - Use NG_WAITOK in syscalls.
  - Remove unneeded includes.
  - style(9)

function, pru_close, to notify protocols that the file descriptor or
other consumer of a socket is closing the socket.  pru_abort is now a
notification of close also, and no longer detaches.  pru_detach is no
longer used to notify of close, and will be called during socket
tear-down by sofree() when all references to a socket evaporate after
an earlier call to abort or close the socket.  This means detach is now
an unconditional teardown of a socket, whereas previously sockets could
persist after detach of the protocol retained a reference.

This faciliates sharing mutexes between layers of the network stack as
the mutex is required during the checking and removal of references at
the head of sofree().  With this change, pru_detach can now assume that
the mutex will no longer be required by the socket layer after
completion, whereas before this was not necessarily true.

Reviewed by:	gnn

we intend for the user to be able to unload them later via kldunload(2)
instead of calling linker_load_module() and then directly adjusting the
ref count on the linker file structure.  This makes the resulting
consumer code simpler and cleaner and better hides the linker internals
making it possible to sanely lock the linker.

Coverity ID:	445