dillo: zlib is a mandatory dependency

Fixes:
http://autobuild.buildroot.net/results/10f/10f7ba386a13753c942139b8bc13ca74d8932f3a/

Also reorder variables a bit and ditch duplicate addition.

Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/dillo/Config.in

@@ -5,6 +5,7 @@ config BR2_PACKAGE_DILLO
 	depends on BR2_USE_MMU # fltk fork()
 	select BR2_PACKAGE_FLTK
 	select BR2_PACKAGE_LIBICONV if !BR2_ENABLE_LOCALE
+	select BR2_PACKAGE_ZLIB
 	help
 	  Dillo is a multi-platform graphical web browser known
 	  for its speed and small footprint.

package/dillo/dillo.mk

@@ -11,13 +11,10 @@ DILLO_LICENSE = GPLv3+
 DILLO_LICENSE_FILES = COPYING
 # For 0001-configure.ac-change-fltk-config-test-to-be-more-cros.patch
 DILLO_AUTORECONF = YES
-
-DILLO_DEPENDENCIES = fltk
-
+DILLO_DEPENDENCIES = fltk zlib \
+	$(if $(BR2_PACKAGE_LIBICONV),libiconv)
 DILLO_CONF_ENV = ac_cv_path_FLTK_CONFIG=$(STAGING_DIR)/usr/bin/fltk-config
 
-DILLO_DEPENDENCIES += $(if $(BR2_PACKAGE_LIBICONV),libiconv)
-
 ifeq ($(BR2_PACKAGE_OPENSSL),y)
 	DILLO_CONF_OPTS += --enable-ssl
 	DILLO_DEPENDENCIES += openssl