DNSRPS builds are broken

From victor dukhovni

The FreeBSD port attempts to build BIND 9.18 after configure ... --enable-dnsrps .... With this enabled, neither BIND 9.18.10 nor 9.18.11 build:

dnsrps.c:945:2: error: incompatible function pointer types initializing 'isc_result_t (*)(dns_db_t *, dns_dbnode_t *, dns_dbversion_t *, unsigned int, isc_stdtime_t, dns_rdatasetiter_t **)' (aka 'enum isc_result (*)(struct dns_db *, void *, void *, unsigned int, unsigned int, struct dns_rdatasetiter **)') with an expression of type 'isc_result_t (dns_db_t *, dns_dbnode_t *, dns_dbversion_t *, isc_stdtime_t, dns_rdatasetiter_t **)' (aka 'enum isc_result (struct dns_db *, void *, void *, unsigned int, struct dns_rdatasetiter **)') [-Werror,-Wincompatible-function-pointer-types]
        rpsdb_allrdatasets,
        ^~~~~~~~~~~~~~~~~~
1 error generated.