ice_diagnostics: remove unused 'rad_to_deg' in diagnostic_abort

Since d673e44 (Clean up code and add several minor features (CICE-Consortium#750),
2022-08-15), the 'rad_to_deg' variable in
ice_diagnostics::diagnostic_abort is unused as the conversion from
radians to degrees is done in 'print_state'.

Remove that local variable as well as the icepack_query_parameters call
used to set it.

cicecore/cicedynB/analysis/ice_diagnostics.F90

@@ -1904,18 +1904,11 @@ subroutine diagnostic_abort(istop, jstop, iblk, stop_label)
 
       ! local variables
 
-      real (kind=dbl_kind) :: rad_to_deg
-
       type (block) :: &
          this_block      ! block information for current block
 
       character(len=*), parameter :: subname = '(diagnostic_abort)'
 
-      call icepack_query_parameters(rad_to_deg_out=rad_to_deg)
-      call icepack_warnings_flush(nu_diag)
-      if (icepack_warnings_aborted()) call abort_ice(error_message=subname, &
-         file=__FILE__, line=__LINE__)
-
       this_block = get_block(blocks_ice(iblk),iblk)
 
       call flush_fileunit(nu_diag)