Now that the parameters to both set_dfp64() and set_dfp128() are exactly the
same, there is no need for an explicit if() statement to determine which
function should be called based upon size. Instead we can simply use the
preprocessor to generate the call to set_dfp##size() directly.

Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20190926185801.11176-8-mark.cave-ayland@ilande.co.uk>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>