Fixing INTL ext in php-fpm for php71

Author: winfried-van-loon

php-fpm/Dockerfile-71

@@ -149,8 +149,8 @@ RUN if [ ${INSTALL_TOKENIZER} = true ]; then \
 # Human Language and Character Encoding Support:
 #####################################
 
-ARG INTL=false
-RUN if [ ${INTL} = true ]; then \
+ARG INSTALL_INTL=false
+RUN if [ ${INSTALL_INTL} = true ]; then \
     # Install intl and requirements
     apt-get install -y zlib1g-dev libicu-dev g++ && \
     docker-php-ext-configure intl && \