softfloat: move float*_eq and float*_eq_quiet

I am not a big fan of code moving, but having the signaling version in
the middle of quiet versions and vice versa doesn't make the code easy
to read.

This patch is a simple code move, basically swapping locations of
float*_eq and float*_eq_quiet.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>