Add do-nothing function |ERR_load_SSL_strings|.

This benefits pyOpenSSL.

Change-Id: Ie7a35d6f9e9a1f0c7fe42ba105c68c327f7d0b0e
Reviewed-on: https://boringssl-review.googlesource.com/5740
Reviewed-by: Adam Langley <agl@google.com>
diff --git a/ssl/ssl_lib.c b/ssl/ssl_lib.c
index 988b3a1..5e322d9 100644
--- a/ssl/ssl_lib.c
+++ b/ssl/ssl_lib.c
@@ -2877,3 +2877,4 @@
 int SSL_CTX_sess_misses(const SSL_CTX *ctx) { return 0; }
 int SSL_CTX_sess_timeouts(const SSL_CTX *ctx) { return 0; }
 int SSL_CTX_sess_cache_full(const SSL_CTX *ctx) { return 0; }
+void ERR_load_SSL_strings(void) {}