tools: fix error path of xenhypfs_open()

In case of an error in xenhypfs_open() the error path will cause a
segmentation fault due to a wrong sequence of closing calls.

Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Fixes: 86234eafb9 ("libs: add libxenhypfs")
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Release-acked-by: Paul Durrant <paul@xen.org>
Acked-by: Wei Liu <wl@xen.org>

tools/libs/hypfs/core.c

@@ -74,8 +74,8 @@ xenhypfs_handle *xenhypfs_open(xentoollog_logger *logger,
     return fshdl;
 
 err:
-    xtl_logger_destroy(fshdl->logger_tofree);
     xencall_close(fshdl->xcall);
+    xtl_logger_destroy(fshdl->logger_tofree);
     free(fshdl);
     return NULL;
 }