Changeset #149c33923f47 broke the architectures that do not
support the --with-float=X ./configure flag (in gcc). For example,
x86_64 does not support it.
Add a new blind config option that architectures can set to tell
they support floating point selection.
Reported-by: Morten Thunberg Svendsen <mts@doredevelopment.dk>
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>