Correct c_sdp_subband_equalizer_latency = 7, to accouint for added msb and lsb pipeline in requantizer.

Rename c_sdp_W_fsub_wg into c_sdp_W_local_oscillator. Use func_wpfb_map_real_input_wpfb_parameters_to_complex_input() to derive c_sdp_wpfb_complex_subbands from c_sdp_wpfb_subbands.

Use c_sdp_FS_adc, c_sdp_wg_ampl_lsb and c_sdp_wg_subband_freq_unit from sdp_pkg.vhd, to make tb code more clean and uniform.

Use c_wpfb_lofar2_subbands_dts_18b setting. Use func_wpfb_subband_gain() to calculate expected subband ampl.