MFC r336027 (andrew): Teach binutils that arm64 is a 64bit architecture.

This is needed to cross build from arm64 to other architectures that
use binutils.

Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Add new PowerPC relocations to binutils

Summary:
LLVM/Clang generates relocations that our binutils doesn't understand, but newer
binutils does. I got permission from the author of a series of patches to
relicense them as GPLv2 for use in FreeBSD. The upstream git hashes are:

ac2df442ac7901f00af15b272fc48b594b433713
2b95367962dc14f69d3c338c4d54195266e2e169
102890f04c44b64cf5cef4588267dd9f24086ac7
b7fcf6f6bb53b5027e111107f5416769cb9a5798
1d483afedd5a628dc84fb58d1d570f79fdfbfa7b
90aecf7a80c1cefeb45fc10a6cd02c8338e34b4c
3a71aa26df2a372a58e9c11ef9ba51fd0e83320a
727fc41e077139570ea8b8ddfd6c546b2a55627c

With the import of clang 3.5, and a few backported patches, we should be able to
move powerpc and powerpc64 to clang-as-cc soon.

Test Plan: Passes make tinderbox, so no regressions. Binaries built with clang
run on powerpc64.

Reviewers: #committers, dim

Reviewed By: dim

Differential Revision: https://reviews.freebsd.org/D1297

Obtained from: Alan Modra, upstream binutils-gdb git
MFC after: 3 weeks
Relnotes: yes

Remove ia64.

This includes:
o All directories named *ia64*
o All files named *ia64*
o All ia64-specific code guarded by __ia64__
o All ia64-specific makefile logic
o Mention of ia64 in comments and documentation

This excludes:
o Everything under contrib/
o Everything under crypto/
o sys/xen/interface
o sys/sys/elf_common.h

Discussed at: BSDcan

Merge binutils 2.17.50 to head. This brings a number of improvements to
x86 CPU support, better support for powerpc64, some new directives, and
many other things. Bump __FreeBSD_version, and add a note to UPDATING.

Thanks to the many people that have helped to test this.

Obtained from: projects/binutils-2.17

Add/improve mips64r2, Octeon, n32 and n64 support in the toolchain.

o) Add TARGET_ABI to the MIPS toolchain build process. This sets the default
ABI to one of o32, n32 or n64. If it is not set, o32 is assumed as that is
the current default.
o) Set the default GCC cpu type to any specified TARGET_CPUTYPE. This is
necessary to have a working "cc" if e.g. mips64 is specified, as binutils
will refuse to link objects using different ISAs in some cases.
o) Add support for n32 and n64 ABIs to binutils and GCC.
o) Add additional required libgcc2 stubs for n32 and n64.
o) Add support for the "mips64r2" architecture to GCC. Add the "octeon"
o) When static linking, wrap default libraries in --start-group and
--end-group. This is required for static linking to work on n64 with the
interdependencies between libraries there. This is what other OSes that
support n64 seem to do, as well.
o) Fix our GCC spec to define __mips64 for 64-bit targets, not __mips64__, the
former being what libgcc, etc., check and the latter seemingly being a
misspelling of a hand merge from a Linux spec.
o) When no TARGET_CPUTYPE is specified at build time, make GCC take the default
ISA from the ABI. Our old defaults were too liberal and assumed that 64-bit
ABIs should default to the MIPS64 ISA and that 32-bit ABIs should default to
the MIPS32 ISA, when we are supporting or will support some systems based on
earlier 32-bit and 64-bit ISAs, most notably MIPS-III.
o) Merge a new opcode file (and support code) from a later version of binutils
and add flags and code necessary to support Octeon-specific instructions.
This should also make merging opcodes for other modern architectures easier.

Reviewed by: imp

Push mips support into the tree.

Fix PowerPC-targeted cross-builds performed on 64-bit platforms.
Only PowerPC supports both 32-bit and 64-bit targets and the
BFD_DEFAULT_TARGET_SIZE is used by the binutils code to reflect
the preferred ABI. We define BFD_DEFAULT_TARGET_SIZE for all
platforms, but based on the build machine. As such 64-bit build
machines defined BFD_DEFAULT_TARGET_SIZE incorrectly for 32-bit
targets, but since this only affects PowerPC it went unnoticed
for a long time.
The fix is to define BFD_DEFAULT_TARGET_SIZE based on the target
architecture.

PR: amd64/102996
MFC after: 1 month

MAJOR cleanup of the Bmake framework.
This includes removing all vestiges of the old not-really supported
ability to build cross tools targeting non-FreeBSD systems, such as
m68k Lynx and NetBSD. Move as much duplicated code from platform
Makefiles into the shared Makefiles. Add a simple mechanism for
specifying ELF 'ldscripts'. Also share as many .h files as possible
(now a single bfd.h vs. one per platform).