Remove X509_REQ's refcount.

We have no X509_REQ_up_ref function, and neither does OpenSSL. That
means this reference count is unreachable, so remove it.

Change-Id: I6a0899b8fcb0716d47c89174b561e90d99a9b54b
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/53306
Reviewed-by: Bob Beck <[email protected]>
Commit-Queue: David Benjamin <[email protected]>
(cherry picked from commit f022e8421b927296d50436ae7b4b54fa4019cf41)

Author: davidben

crypto/x509/internal.h

@@ -181,7 +181,6 @@ struct X509_req_st {
   X509_REQ_INFO *req_info;
   X509_ALGOR *sig_alg;
   ASN1_BIT_STRING *signature;
-  CRYPTO_refcount_t references;
 } /* X509_REQ */;
 
 struct x509_revoked_st {

crypto/x509/x_req.c

@@ -105,11 +105,11 @@ ASN1_SEQUENCE_enc(X509_REQ_INFO, enc, rinf_cb) = {
 
 IMPLEMENT_ASN1_FUNCTIONS(X509_REQ_INFO)
 
-ASN1_SEQUENCE_ref(X509_REQ, 0) = {
+ASN1_SEQUENCE(X509_REQ) = {
     ASN1_SIMPLE(X509_REQ, req_info, X509_REQ_INFO),
     ASN1_SIMPLE(X509_REQ, sig_alg, X509_ALGOR),
     ASN1_SIMPLE(X509_REQ, signature, ASN1_BIT_STRING),
-} ASN1_SEQUENCE_END_ref(X509_REQ, X509_REQ)
+} ASN1_SEQUENCE_END(X509_REQ)
 
 IMPLEMENT_ASN1_FUNCTIONS(X509_REQ)