patman: Add support for building a u_boot_tools PyPi package

Create the necessary files to build this new package.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/tools/u_boot_pylib/README.rst b/tools/u_boot_pylib/README.rst
new file mode 100644
index 0000000..93858f5
--- /dev/null
+++ b/tools/u_boot_pylib/README.rst
@@ -0,0 +1,15 @@
+.. SPDX-License-Identifier: GPL-2.0+
+
+# U-Boot Python Library
+=====================
+
+This is a Python library used by various U-Boot tools, including patman,
+buildman and binman.
+
+The module can be installed with pip::
+
+   pip install u_boot_pylib
+
+or via setup.py::
+
+   ./setup.py install [--user]