crypto: add missing return value check

Add return value check for call to SSL_CTX_add_client_CA
to be consistent with other places it is called

Fixed unused warning in one of the static analysis tools we use
at Red Hat even though it is not being reported by coverity in
the configuration we run.

Signed-off-by: Michael Dawson <midawson@redhat.com>
PR-URL: #56615
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

src/crypto/crypto_context.cc

@@ -1164,7 +1164,7 @@ void SecureContext::LoadPKCS12(const FunctionCallbackInfo<Value>& args) {
     X509* ca = sk_X509_value(extra_certs.get(), i);
 
     X509_STORE_add_cert(sc->GetCertStoreOwnedByThisSecureContext(), ca);
-    SSL_CTX_add_client_CA(sc->ctx_.get(), ca);
+    CHECK_EQ(1, SSL_CTX_add_client_CA(sc->ctx_.get(), ca));
   }
   ret = true;