use_versioned_archname => versionedarchname

use_versioned_archname => versionedarchname

backport of ba95ddbf39c3f4434439

This patch adds 'use_versioned_archname' as a Configure option.
When set, it includes 'api_versionstring' in 'archname'. E.g.
x86_64-linux-5.13.6-thread-multi.  It is unset by default.

This feature was requested by Tim Bunce, who observed that
INSTALL_BASE creates a library structure that does not
differentiate by perl version.  Instead, it places architecture
specific files in "$install_base/lib/perl5/$archname".  This makes
it difficult to use a common INSTALL_BASE library path with
multiple versions of perl.

By setting -Duse_versioned_archname, the $archname will be
distinct for architecture *and* API version, allowing mixed use of
INSTALL_BASE.

This patch demonstrates the desired effect for discussion.  Actual
changes would need to be made upstream in metaconfig and
integrated back into blead.