Makefile.am: add program to compute p of instruments given horizon

gstlal-inspiral/bin/Makefile.am

@@ -8,6 +8,7 @@ dist_bin_SCRIPTS = \
 	gstlal_inspiral_calc_rank_pdfs \
 	gstlal_inspiral_coinc_extractor \
 	gstlal_inspiral_create_dt_dphi_snr_ratio_pdfs \
+	gstlal_inspiral_create_p_of_ifos_given_horizon \
 	gstlal_inspiral_create_prior_diststats \
 	gstlal_inspiral_dlrs_diag \
 	gstlal_inspiral_fake_zerolag_counts \