external/boringssl: Sync to 8ca0b41.

This includes the following changes:

https://boringssl.googlesource.com/boringssl/+log/9d908ba519f2cfe5e21561bdee3e224b94d14a89..8ca0b4127da11d766067ea6ec4122017ba0edb0e

Change-Id: I732653bc8fcba70707c615f8731ca75397a08736
diff --git a/src/crypto/thread_none.c b/src/crypto/thread_none.c
index cf4e85a..85768b4 100644
--- a/src/crypto/thread_none.c
+++ b/src/crypto/thread_none.c
@@ -22,7 +22,9 @@
 
 void CRYPTO_MUTEX_lock_write(CRYPTO_MUTEX *lock) {}
 
-void CRYPTO_MUTEX_unlock(CRYPTO_MUTEX *lock) {}
+void CRYPTO_MUTEX_unlock_read(CRYPTO_MUTEX *lock) {}
+
+void CRYPTO_MUTEX_unlock_write(CRYPTO_MUTEX *lock) {}
 
 void CRYPTO_MUTEX_cleanup(CRYPTO_MUTEX *lock) {}
 
@@ -30,7 +32,9 @@
 
 void CRYPTO_STATIC_MUTEX_lock_write(struct CRYPTO_STATIC_MUTEX *lock) {}
 
-void CRYPTO_STATIC_MUTEX_unlock(struct CRYPTO_STATIC_MUTEX *lock) {}
+void CRYPTO_STATIC_MUTEX_unlock_read(struct CRYPTO_STATIC_MUTEX *lock) {}
+
+void CRYPTO_STATIC_MUTEX_unlock_write(struct CRYPTO_STATIC_MUTEX *lock) {}
 
 void CRYPTO_once(CRYPTO_once_t *once, void (*init)(void)) {
   if (*once) {