tools: Make list.h self-sufficient

Commit 7f5f873 ("rculist: Use WRITE_ONCE() when deleting from
reader-visible list") added the use of the WRITE_ONCE macro to the
kernel version of list.h, which broke the stacktool build because the
tools list.h includes the kernel list.h.

Avoid this type of situation in the future and make list.h
self-sufficient by copying the kernel list.h routines directly into
tools list.h.

This is a straight copy except for adjustments to the include statements
and copying of the tools-specific list routines (list_del_range and
list_for_each_from).

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Chris J Arges <chris.j.arges@canonical.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/59cdc19c6589d1b5ef43d83b0e2d5a4a40301374.1450442274.git.jpoimboe@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>