Add X509_PUBKEY to bssl::UniquePtr.

Change-Id: I02d5c8f4a84facc2b120abc3268fb316670b7986
Reviewed-on: https://boringssl-review.googlesource.com/19804
Commit-Queue: David Benjamin <davidben@google.com>
Commit-Queue: Matt Braithwaite <mab@google.com>
Reviewed-by: Matt Braithwaite <mab@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>

include/openssl/x509.h

diff --git a/include/openssl/x509.h b/include/openssl/x509.h
index 138c060..62bd5f8 100644
--- a/include/openssl/x509.h
+++ b/include/openssl/x509.h
@@ -1113,6 +1113,7 @@
 BORINGSSL_MAKE_DELETER(X509_NAME_ENTRY, X509_NAME_ENTRY_free)
 BORINGSSL_MAKE_DELETER(X509_PKEY, X509_PKEY_free)
 BORINGSSL_MAKE_DELETER(X509_POLICY_TREE, X509_policy_tree_free)
+BORINGSSL_MAKE_DELETER(X509_PUBKEY, X509_PUBKEY_free)
 BORINGSSL_MAKE_DELETER(X509_REQ, X509_REQ_free)
 BORINGSSL_MAKE_DELETER(X509_REVOKED, X509_REVOKED_free)
 BORINGSSL_MAKE_DELETER(X509_SIG, X509_SIG_free)