fix decomposition issue with cimin

[junwang-noaa]

This PR is to fix the decomposition issue associated with cimin in radiation surface physics.

The following code sets cimin to the last cimin value from im, if decomposition changed, the cimin could get different value.

  do i=1,im
    if (lakefrac(i) > f_zero) then
      cimin = min_lakeice
    else
      cimin = min_seaice
    endif
  enddo

[climbfuji]

Excellent find, @junwang-noaa - thanks also for fixing this in RUC LSM. I will add @tanyasmirnova as reviewer.

[SMoorthi-emc]

This is not just a decomposition issue - it is a real bug using the same cimin for all IM points!

[tanyasmirnova]

I agree with this bug fix. Thank you, @junwang-noaa