build: simplify BLAS library detection in configure (bug #62715) * configure.ac: Replace calls to OCTAVE_BLAS_F77_FUNC with OCTAVE_BLAS. * m4/octave_blas_f77_func.m4: Removed obsolete macro file. * m4/octave_blas.m4: New file with OCTAVE_BLAS macro to detect BLAS library and find size of integers in library. * m4/module.mk: Add octave_blas.m4 to build system.

%!function out = bug54490 ()
%!  global k;
%!  k = 1;
%!  out = 3;
%!endfunction

%!test <*54490>
%! global k;
%! k = 2;
%! a = [5, 6];
%! a(k) = bug54490 ();
%! assert (a, [5, 3]);
%! k = 2;
%! a = [5, 6];
%! [a(k)] = bug54490 ();
%! assert (a, [5, 3]);
%! clear -global k;  # cleanup after test