Functions in ivas_omasa_dec.c converted to fixed point.

[x] Ported ivas_omasa_data_open, ivas_omasa_data_close,
ivas_dirac_dec_binaural_internal(partial), generate_masking_noise_dirac,
ivas_combined_orientation_update_index, resampleCldfb_ivas, rand_gauss,
v_multc_32_16_fixed, generate_masking_noise_dirac functions