unbound: Fix crash of daemon at startup

getentropy() cannot be used on our platform.

Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>

lfs/unbound

@@ -79,7 +79,8 @@ $(TARGET) : $(patsubst %,$(DIR_DL)/%,$(objects))
 			--with-rootkey-file=/var/lib/unbound/root.key \
 			--disable-static \
 			--with-libevent \
-			--enable-event-api
+			--enable-event-api \
+			ac_cv_func_getentropy=no
 
 	cd $(DIR_APP) && make $(MAKETUNING)
 	cd $(DIR_APP) && make install