fix, build silently dropped flag --without-ecc

setup.py

@@ -19,7 +19,7 @@ class prepare_tinydtls(build_ext):
         commands =  [
                     ["sh", "-c", "autoconf"],
                     ["sh", "-c", "autoheader"],
-                    ["sh", "-c", "./configure", "--without-ecc"],
+                    ["sh", "-c", "./configure --without-ecc"],
                     ]
         if not os.path.exists(os.path.join(os.path.dirname(__file__), 'DTLSSocket','tinydtls','dtls.c')):
             run_command(["git", "submodule", "update", "--init"])