Fix unused goto label gcc warning

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