libressl: fix compile for uClibc-ng linuxthreads targets, reported by Mario

package/libressl/Makefile

@@ -5,7 +5,7 @@ include $(ADK_TOPDIR)/rules.mk
 
 PKG_NAME:=		libressl
 PKG_VERSION:=		2.4.2
-PKG_RELEASE:=		1
+PKG_RELEASE:=		2
 PKG_HASH:=		5f87d778e5d62822d60e38fa9621c1c5648fc559d198ba314bd9d89cbf67d9e3
 PKG_DESCR:=		ssl/tls library
 PKG_SECTION:=		libs/crypto

package/libressl/patches/patch-crypto_compat_arc4random_linux_h

@@ -0,0 +1,11 @@
+--- libressl-2.4.2.orig/crypto/compat/arc4random_linux.h	2016-08-01 01:07:36.000000000 +0200
++++ libressl-2.4.2/crypto/compat/arc4random_linux.h	2016-10-17 21:56:49.830938238 +0200
+@@ -32,7 +32,7 @@ static pthread_mutex_t arc4random_mtx =
+ #define _ARC4_LOCK()   pthread_mutex_lock(&arc4random_mtx)
+ #define _ARC4_UNLOCK() pthread_mutex_unlock(&arc4random_mtx)
+ 
+-#ifdef __GLIBC__
++#if defined(__GLIBC__) && !defined(__UCLIBC__)
+ extern void *__dso_handle;
+ extern int __register_atfork(void (*)(void), void(*)(void), void (*)(void), void *);
+ #define _ARC4_ATFORK(f) __register_atfork(NULL, NULL, (f), __dso_handle)