package/botan: fix boost dependency

only build --with-boost when both required modules (filesystem and system) are
also selected.

Fixes:
http://autobuild.buildroot.net/results/4fbf2a63f9ddfbc540ce7dabd10964b311477c06

Signed-off-by: Michael Nosthoff <buildroot@heine.tech>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>

package/botan/botan.mk

@@ -53,7 +53,7 @@ ifeq ($(BR2_TOOLCHAIN_USES_UCLIBC),y)
 BOTAN_CONF_OPTS += --without-os-feature=getauxval
 endif
 
-ifeq ($(BR2_PACKAGE_BOOST),y)
+ifeq ($(BR2_PACKAGE_BOOST_FILESYSTEM)$(BR2_PACKAGE_BOOST_SYSTEM),yy)
 BOTAN_DEPENDENCIES += boost
 BOTAN_CONF_OPTS += --with-boost
 endif