patch around opendmarc API change introduced in
https://github.com/trusteddomainproject/OpenDMARC/commit/dbd87868f2ca9c2ef11529cd757d1cc5ab228833

Index: src/dmarc.c
--- src/dmarc.c.orig
+++ src/dmarc.c
@@ -459,7 +459,7 @@ if (!dmarc_abort && !sender_host_authenticated)
 		  vs == PDKIM_VERIFY_INVALID ? DMARC_POLICY_DKIM_OUTCOME_TMPFAIL :
 		  DMARC_POLICY_DKIM_OUTCOME_NONE;
     libdm_status = opendmarc_policy_store_dkim(dmarc_pctx, US sig->domain,
-					       dkim_result, US"");
+					       sig->selector, dkim_result, US"");
     DEBUG(D_receive)
       debug_printf("DMARC adding DKIM sender domain = %s\n", sig->domain);
     if (libdm_status != DMARC_PARSE_OKAY)