package/libtorrent: requires RC4 support in openssl

Enable RC4 in openssl to fix build failure raised since commit
a83d41867c8d69a77d5cd0a665aa216af5340359

Fixes:
 - http://autobuild.buildroot.org/results/c909fedb5f59d8a434a3bde469155ff550615e3c

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>

package/libtorrent/Config.in

@@ -4,6 +4,7 @@ config BR2_PACKAGE_LIBTORRENT
 	depends on BR2_TOOLCHAIN_HAS_THREADS
 	depends on BR2_TOOLCHAIN_HAS_SYNC_1 && BR2_TOOLCHAIN_HAS_SYNC_4
 	select BR2_PACKAGE_ZLIB
+	select BR2_PACKAGE_LIBOPENSSL_ENABLE_RC4 if BR2_PACKAGE_LIBOPENSSL
 	help
 	  BitTorrent library written in C++ for *nix