resolved: add SHA384 digest support

src/resolve/resolved-dns-dnssec.c

@@ -742,6 +742,9 @@ static int digest_to_gcrypt(uint8_t algorithm) {
         case DNSSEC_DIGEST_SHA256:
                 return GCRY_MD_SHA256;
 
+        case DNSSEC_DIGEST_SHA384:
+                return GCRY_MD_SHA384;
+
         default:
                 return -EOPNOTSUPP;
         }

src/resolve/resolved-dns-rr.h

@@ -64,6 +64,7 @@ enum {
 enum {
         DNSSEC_DIGEST_SHA1 = 1,
         DNSSEC_DIGEST_SHA256 = 2,
+        DNSSEC_DIGEST_SHA384 = 4,
         _DNSSEC_DIGEST_MAX_DEFINED
 };