lang/rust: Install Cargo + use bundled crates

This port now provides Cargo. This is the recommended now because Cargo
won't be provided separately in the future.

To build Cargo, we set extended = true in config.toml. As a side
effect, this flag also installs Rust source code. The port has a new
SOURCES option (disabled by default) to keep those sources.

As a consequence of this, devel/cargo is removed. Several ports
and Makefiles in Mk were updated to depend on lang/rust instead of
devel/cargo.

The other big change in this patch is the use of the bundled crates,
instead of relying on Cargo's registry (which was part of the distfiles,
in order to allow offline builds). So now, we don't need to prepare the
registry when updating this port.

This has several other benefits:

• It fixes the build with sudo(8).
• It fixes the use of the ino-64 patch (it was not applied to the registry, thus not used).

Compilation errors were fixed in the ino-64 patch.

Various .cargo-checksum.json files are updated after the sources are
patched (FBSD10_FIX, ino-64, and so on). This fixes builds which were
failing with errors such as:

error: the listed checksum of `.../rustc-1.19.0-src/src/vendor/lzma-sys/xz-5.2.3/build-aux/config.rpath` has changed:
expected: c8b4c017079da9dfb3086a0583e60ffe736184d89005dc5973f0bb0fd17c04bb
actual:   561b00eb30ecaef2c9da17bc195e7d2a7ea63facea38ea9849fbb0ed340bebba

PR: 221088
Reported by: joneum@, nwhitehorn@, romain@,

		Ekaterina Vaartis <vaartis@cock.li>,
		david@catwhisker.org,
		fullermd@over-yonder.net,
		rum1cro@yandex.ru,
		w.schwarzenfeld@utanet.at

Differential Revision: https://reviews.freebsd.org/D11783