[Bug libfortran/48925] Code cleanup in write_float.def

[jvdelisle at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48925

--- Comment #3 from Jerry DeLisle <jvdelisle at gcc dot gnu.org> ---
Lets first fix the known bugs so we have a good baseline.  Then we can
reorganize the code with little impact And with with additional test cases fro
those bug fixes, we minimize our probability of regressions.