Initialize worka for sifb (#1092)

Minor fix to initialize worka=0 for sifb history variable accumulation (like elsewhere in ice_history) so don't have uninitialized values being accumulated. This is needed to fix out-of-range history values for sifb (in UFS)

Author: NickSzapiro-NOAA

cicecore/cicedyn/analysis/ice_history.F90

@@ -3064,6 +3064,7 @@ subroutine accum_hist (dt)
          endif
 
          if (f_sifb(1:1) /= 'x') then
+           worka(:,:) = c0
            do j = jlo, jhi
            do i = ilo, ihi
               if (aice(i,j,iblk) > puny) then