Fixed phpize build (default PHP_OPENSSL to no if not set)

ext/ftp/config.m4

@@ -12,6 +12,9 @@ if test "$PHP_FTP" = "yes"; then
   AC_DEFINE(HAVE_FTP,1,[Whether you want FTP support])
   PHP_NEW_EXTENSION(ftp, php_ftp.c ftp.c, $ext_shared)
 
+  dnl Empty variable means 'no'
+  test -z "$PHP_OPENSSL" && PHP_OPENSSL=no
+
   if test "$PHP_OPENSSL" != "no" || test "$PHP_OPENSSL_DIR" != "no"; then
     PHP_SETUP_OPENSSL(FTP_SHARED_LIBADD)
     PHP_SUBST(FTP_SHARED_LIBADD)