Also add a no-op stub for OPENSSL_config.

Apparently OpenSSL's API is made entirely of initialization functions.
Some external libraries like to initialize with OPENSSL_config instead.

Change-Id: I28efe97fc5eb21309f560c84112b80e947f8bb17
Reviewed-on: https://boringssl-review.googlesource.com/6981
Reviewed-by: Adam Langley <agl@google.com>
diff --git a/crypto/conf/conf.c b/crypto/conf/conf.c
index 7512dd0..6bdcc4d 100644
--- a/crypto/conf/conf.c
+++ b/crypto/conf/conf.c
@@ -783,3 +783,5 @@
 }
 
 void CONF_modules_free(void) {}
+
+void OPENSSL_config(CONF_MUST_BE_NULL *config_name) {}
diff --git a/include/openssl/conf.h b/include/openssl/conf.h
index 0d2b61d..75f14f5 100644
--- a/include/openssl/conf.h
+++ b/include/openssl/conf.h
@@ -152,6 +152,9 @@
 /* CONF_modules_free does nothing. */
 OPENSSL_EXPORT void CONF_modules_free(void);
 
+/* OPENSSL_config does nothing. */
+OPENSSL_EXPORT void OPENSSL_config(CONF_MUST_BE_NULL *config_name);
+
 
 #if defined(__cplusplus)
 }  /* extern C */