Fix build after addition of RSA_get0_key() to LibreSSL.

ok sthen

sysutils/u-boot/patches/patch-tools_kwbimage_c

@@ -0,0 +1,23 @@
+$OpenBSD: patch-tools_kwbimage_c,v 1.3 2018/02/19 21:46:28 tb Exp $
+
+Index: tools/kwbimage.c
+--- tools/kwbimage.c.orig
++++ tools/kwbimage.c
+@@ -24,7 +24,7 @@
+ #include <openssl/err.h>
+ #include <openssl/evp.h>
+ 
+-#if OPENSSL_VERSION_NUMBER < 0x10100000L || defined(LIBRESSL_VERSION_NUMBER)
++#if OPENSSL_VERSION_NUMBER < 0x10100000L
+ static void RSA_get0_key(const RSA *r,
+                  const BIGNUM **n, const BIGNUM **e, const BIGNUM **d)
+ {
+@@ -36,7 +36,7 @@ static void RSA_get0_key(const RSA *r,
+        *d = r->d;
+ }
+ 
+-#else
++#elif !defined(LIBRESSL_VERSION_NUMBER)
+ void EVP_MD_CTX_cleanup(EVP_MD_CTX *ctx)
+ {
+ 	EVP_MD_CTX_reset(ctx);