Toplevel cleanup: disable Java when libffi not supported

[Joseph S. Myers]

On Thu, 28 Apr 2011, Paolo Bonzini wrote:

> Do you plan to finish the switch to unsupported_languages instead of
> noconfigdirs soon )for Java)?

I plan one further patch to simplify the libgcj-disabling logic (and in 
particular to eliminate the disabling for *-*-*), but not to convert it 
completely to unsupported_languages.  I also plan to split the 
newlib/libgloss logic out of the general case statement over targets, as 
part of further simplifications there.  I don't plan to work on the 
general elimination of target-libiberty.

-- 
Joseph S. Myers
joseph@codesourcery.com