Fix |SSLeay|.

SSLeay is a compatibility function for OpenSSL, but I got it wrong. It
doesn't return a string, it returns a number. This doesn't end up making
any difference, but it fixes a warning when building OpenSSH.

Change-Id: I327ab4f70313c93c18f81d8804ba4acdc3bc1a4a
Reviewed-on: https://boringssl-review.googlesource.com/4811
Reviewed-by: David Benjamin <davidben@chromium.org>
Reviewed-by: Adam Langley <agl@google.com>
diff --git a/crypto/crypto.c b/crypto/crypto.c
index 64e55f4..d9bb07e 100644
--- a/crypto/crypto.c
+++ b/crypto/crypto.c
@@ -104,9 +104,9 @@
 }
 
 const char *SSLeay_version(int unused) {
-  return SSLeay();
+  return "BoringSSL";
 }
 
-const char *SSLeay(void) {
-  return "BoringSSL";
+unsigned long SSLeay(void) {
+  return OPENSSL_VERSION_NUMBER;
 }