scripts: Fixes deprecated use of --with-relaxed

* From
  nteract/nteract#1189 (comment)

* See
  zeromq/libzmq@7129187

Author: n-riesco

scripts/build_libzmq.sh

@@ -21,7 +21,11 @@ test -d "${ZMQ_SRC_DIR}" || tar xzf zeromq-$ZMQ.tar.gz
 cd "${ZMQ_SRC_DIR}"
 
 test -f configure || ./autogen.sh
-./configure "--prefix=${ZMQ_PREFIX}" --with-relaxed --enable-static --disable-shared
+if [ "$ZMQ" = "4.1.6" ]; then
+  ./configure "--prefix=${ZMQ_PREFIX}" --with-relaxed --enable-static --disable-shared ;
+else
+  ./configure "--prefix=${ZMQ_PREFIX}" --disable-pedantic --enable-static --disable-shared ;
+fi
 make -j 2
 make install