Generalize the ILP64 BLAS/LAPACK symbol name handling to deal with
arbitrary prefix/suffix.

The build-time behavior is changed so that HAVE_BLAS_ILP64 and
BLAS_SYMBOL_SUFFIX/PREFIX defines are added to compile options
as appropriate.

Mainly to make autodetection of BLAS/LAPACK easier for downstream
numpy.distutils users, add get_info aliases 'blas_ilp64_opt',
'blas_ilp64_plain_opt', and 'blas64__opt' for any/no/""&"64_"
prefix&suffix, and the same for lapack. (Due to the way system_info
works, each also gets a separate class.)

In addition to openblas64_ which has a fixed suffix, add the (by default
suffixless) openblas_ilp64, which correspond to the most likely cases to
be present.

This is an emerging "standard" for 64-bit BLAS/LAPACK, avoiding symbol
clashes with 32-bit BLAS/LAPACK, originally introduced for Julia.
OpenBLAS can be compiled with 64-bit integer size and symbol suffix
'64_' (INTERFACE64=1 SYMBOLSUFFIX=64_).  OpenBLAS built with this
setting is also provided by some Linux distributions (e.g. Fedora's
64-bit openblas packages).

Now libflame may be used as a LAPACK back-end.
libflame requires an external BLAS so one has to
also have this enabled.
Also added release notes for NPY_*_ORDER and libFLAME.

* BLD: use libraries as a key consistently in all site.cfg sections

BUG: parse shell escaping in extra_compile_args and extra_link_args

Thanks to a change in exec_command, these strings are no longer passed onto the shell.
Since config files do not support list values, our best bet is to perform shell-splitting immediately.

This brings the behavior back in line a little to how it was before.

On windows systems, the behavior has changed. Previously it was treated as a single argument unless it contained quotes, resulting in the following weird behavior:

    # passes as one argument, preserving spaces
    extra_link_args=-Wl,rpath=A:/path/with spaces
    # passes as two arguments, preserving spaces
    extra_link_args="-Wl,rpath=A:\path\with spaces" -lgfortran
    # passes as one long quoted argument (surprising and undesirable)
    extra_link_args=-Wl,rpath=A:\path\without_spaces -lgfortran

Now it behaves as windows escaping via subprocess (but _not_ via cmd) normally would:

    # Passed as two separate arguments (probably not as intended, but should be expected)
    extra_link_args=-Wl,rpath=A:/path/with spaces
    # passes as two arguments, preserving spaces
    extra_link_args="-Wl,rpath=A:\path\with spaces" -lgfortran
    # passes as two arguments
    extra_link_args=-Wl,rpath=A:\path\without_spaces -lgfortran

Fixes gh-12659

[ci skip]