g_malloc0_n is available since glib-2.24. To allow build with older glib
versions use the generic g_new0, which is already used in many other
places in the code.
Fixes commit 3284fad728 ("xen-disk: add support for multi-page shared rings")
Signed-off-by: Olaf Hering <olaf@aepfle.de>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>