build: Create octave.desktop even when --disable-docs configured (bug #42720). * etc/icons/Makefile.am, etc/icons/octave-logo.ico, etc/icons/octave-logo.png, etc/icons/octave-logo.svg, etc/icons/octave-sombrero.png, etc/icons/octave.desktop.in, etc/icons/octave_branding_samples.svg: Move doc/icons files to /etc/icons directory. * Makefile.am: Add etc/icons to list of SUBDIRS to build. * configure.ac: Change doc/icons to etc/icons. * doc/Makefile.am: Remove icons from list of SUBDIRS to build.

%!function r = f1 ()
%!  ls = svd (1);
%!  r = eval ("ls -1;");
%!endfunction
%!function r = f2 ()
%!  [u,ls,v] = svd (1);
%!  r = eval ("ls -1;");
%!endfunction
%!function r = f3 (ls)
%!  r = eval ("ls -1;");
%!endfunction

%!test
%! ## Windows systems can't run "ls -1"
%! if (! ispc ())
%!   assert (f1 (), 0);
%!   assert (f2 (), 0);
%!   assert (ischar (f3 ()), true);
%!   assert (f3 (1), 0);
%! endif