Build PDO odbc on azure

We already install the necessary libs for the odbc extension, so
we may as well build PDO ODBC.

As we don't setup an ODBC server, the tests will be skipped.

Close phpGH-6528.

Author: nikic

azure/configure.yml

@@ -61,6 +61,7 @@ steps:
         --with-imap \
         --with-kerberos \
         --with-imap-ssl \
+        --with-pdo-odbc=unixODBC,/usr \
         --enable-werror \
         --with-config-file-path=/etc \
         --with-config-file-scan-dir=/etc/php.d