Fix unused goto label gcc warning

On systems with undefined AI_ADDRCONFIG and AI_NUMERICHOST:

x86_64-w64-mingw32-gcc  -I. -Icrypto/include -Iinclude -m64 -Wall -O3 -fno-ident ...
crypto/bio/b_addr.c: In function 'BIO_lookup_ex':
crypto/bio/b_addr.c:699:7: warning: label 'retry' defined but not used [-Wunused-label]
       retry:
       ^~~~~

Regression from: 3f91ede9aea70774d9b5d509bc76d484ebaff6aa
Reviewed-by: NPaul Dale <paul.dale@oracle.com>
Reviewed-by: NMatthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
(Merged from https://github.com/openssl/openssl/pull/9856)

(cherry picked from commit be66a15cc1a4c3cc68fa854ceea321ca57f96304)

crypto/bio/b_addr.c

@@ -696,7 +696,9 @@ int BIO_lookup_ex(const char *host, const char *service, int lookup_type,
         /* Note that |res| SHOULD be a 'struct addrinfo **' thanks to
          * macro magic in bio_local.h
          */
+# if defined(AI_ADDRCONFIG) && defined(AI_NUMERICHOST)
       retry:
+# endif
         switch ((gai_ret = getaddrinfo(host, service, &hints, res))) {
 # ifdef EAI_SYSTEM
         case EAI_SYSTEM: