Compile error with ngtcp2 #9204

  CC       vtls/libcurl_la-wolfssl.lo
  CC       vtls/libcurl_la-x509asn1.lo
  CC       vquic/libcurl_la-msh3.lo
  CC       vquic/libcurl_la-ngtcp2.lo
vquic/ngtcp2.c: In function ‘ng_flush_egress’:
vquic/ngtcp2.c:1942:12: error: void value not ignored as it ought to be
 1942 |         rv = nghttp3_conn_block_stream(qs->h3conn, stream_id);
      |            ^
vquic/ngtcp2.c:1951:12: error: void value not ignored as it ought to be
 1951 |         rv = nghttp3_conn_shutdown_stream_write(qs->h3conn, stream_id);
      |            ^
make[2]: *** [Makefile:3054: vquic/libcurl_la-ngtcp2.lo] Error 1
make[2]: Leaving directory '/var/build-git2/curl/lib'
make[1]: *** [Makefile:1363: all] Error 2
make[1]: Leaving directory '/var/build-git2/curl/lib'
make: *** [Makefile:1237: all-recursive] Error 1