contrib: nettle 3.4.1 is required

Since we use gnutls 3.6.5, nettle 3.4.1 is required to build the
daemon.

Change-Id: I0041791b8587d63d469e6d24137160e93d3a3893

contrib/src/nettle/rules.mak

@@ -5,7 +5,7 @@ NETTLE_URL := $(GNU)/nettle/nettle-$(NETTLE_VERSION).tar.gz
 
 PKGS += nettle
 
-ifeq ($(call need_pkg,"nettle >= 3.3"),)
+ifeq ($(call need_pkg,"nettle >= 3.4.1"),)
 PKGS_FOUND += nettle
 endif