Add func_sdp_verify_cep_header() variant with beamlet_index_mod.

...2_unb2b_sdp_station_bf/tb_lofar2_unb2b_sdp_station_bf.vhd

...2_unb2c_sdp_station_bf/tb_lofar2_unb2c_sdp_station_bf.vhd

...p_station_bf_ring/tb_lofar2_unb2c_sdp_station_bf_ring.vhd

applications/lofar2/libraries/sdp/tb/vhdl/tb_sdp_pkg.vhd