Add some more compatibility functions.

Change-Id: I56afcd896cb9de1c69c788b4f6395f4e78140d81
Reviewed-on: https://boringssl-review.googlesource.com/28265
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: Adam Langley <agl@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>

crypto/err/err.c

diff --git a/crypto/err/err.c b/crypto/err/err.c
index c7bff16..43d3909 100644
--- a/crypto/err/err.c
+++ b/crypto/err/err.c
@@ -781,6 +781,8 @@
 
 void ERR_load_ERR_strings(void) {}
 
+void ERR_load_RAND_strings(void) {}
+
 struct err_save_state_st {
   struct err_error_st *errors;
   size_t num_errors;