hadrian: Add reloc-binary-dist-* targets

This adds a command line option to build a "relocatable" bindist.

The bindist is created by first creating a normal bindist and then
installing it using the `RelocatableBuild=YES` option. This creates a
bindist without any wrapper scripts pointing to the libdir.

The motivation for this feature is that we want to ship relocatable
bindists on windows and this method is more uniform than the ad-hoc
method which lead to bugs such as #23608 and #23476

The relocatable bindist can be built with the "reloc-binary-dist" target
and supports the same suffixes as the normal "binary-dist" command to
specify the compression style.