crypto: more compact solution to detect endless loop

src/crypto/crypto_common.cc

@@ -480,17 +480,14 @@ MaybeLocal<Object> GetLastIssuedCert(
       return MaybeLocal<Object>();
     issuer_chain = ca_info;
 
-    // Take the value of cert->get() before and after the call to cert->reset()
-    // in order to compare them and provide a way to exit this loop
-    // in case it gets stuck
-    X509* value_before_reset = cert->get();
+    // Take the value of cert->get(), compare it with the value of ca
+    // and provide a way to exit this loop
+    // in case it gets stuck.
+    if (cert->get() == ca)
+      break;
 
     // Delete previous cert and continue aggregating issuers.
     cert->reset(ca);
-
-    X509* value_after_reset = cert->get();
-    if (value_before_reset == value_after_reset)
-      break;
   }
   return MaybeLocal<Object>(issuer_chain);
 }