ldns: update to 1.7.1

squash commits
- add Eric Luehrsen as maintainer
- add ldns-example programs as option
- add ECDSA to support DNSSEC zones with these keys
- remove patches included upstream

Signed-off-by: Eric Luehrsen <ericluehrsen@gmail.com>

libs/ldns/patches/001-compile-for-darwin.patch

@@ -0,0 +1,13 @@
+--- a/configure.ac
++++ b/configure.ac
+@@ -859,10 +859,10 @@
+ AC_ARG_WITH(xcode-sdk, AC_HELP_STRING([--with-xcode-sdk], 
+  [Set xcode SDK version. Default is autodetect]), 
+  [],[with_xcode_sdk="yes"])
+ if test "x_$with_xcode_sdk" != "x_no" ; then
+    # check OSX deployment target, if needed
+-   if echo $build_os | grep darwin > /dev/null; then
++   if echo $target_os | grep darwin > /dev/null; then
+      sdk_p=`xcode-select -print-path`;
+      if test "x_$with_xcode_sdk" = "x_yes" ; then
+         sdk_v="$( /usr/bin/xcrun --show-sdk-version 2>/dev/null )"