[Bug fortran/69121] IEEE_SCALB is not generic

[kargl at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69121

--- Comment #1 from kargl at gcc dot gnu.org ---
This is easy to fix by adding the appropriate code to
libgfortran/ieee/ieee_arithmetic.F90.

% svn diff ieee_arithmetic.F90 | wc -l
  225