A few potentially disruptive changes:

- binutils does not embed ${binutils-unwrapped}/lib as a default library
  search path anymore. This will cause link failures for -lbfd -lopcodes
  users that did not declare their dependency on those libraries. They
  will need to add `libbfd` and `libopcodes` attributes to build inputs.

- `libbfd` and `libopcodes` attributes now just reference
  `binutils-unwrapped.{dev,lib}` pair of attributes without patching
  `binutils` build system.

We don't patch build system anymore and use multiple outputs out of
existing `binutils` build. That makes the result more maintainable: no
need to handle ever growing list of dependencied of `libbfd`. This time
new addition was `libsframe`.

To accomodate `out` / `lib` output split I had to remove `lib` -> `bin`
backreference by removing legacy lookup path for plugins.

I also did not enable `zstd` just yet as `nixpkgs` version of `zstd`
package pulls in `cmake` into bootstrap sequence.

Changes: https://lists.gnu.org/archive/html/info-gnu/2023-01/msg00003.html