doc: integrate config xsl transform into doc build

Documentation for the scenario XML configuration options is pulled from the
schema definition files (xsd) maintained in the misc/config_tools/schema
folder.  Update the doc build process to generate and incorporate the
option documentation.

Signed-off-by: David B. Kinder <david.b.kinder@intel.com>

doc/reference/config-options.rst

@@ -0,0 +1,41 @@
+.. _scenario-config-options:
+
+Scenario Configuration Options
+##############################
+
+As explained in :ref:`acrn_configuration_tool`, ACRN scenarios define
+the hypervisor (hv) and VM settings for the execution environment of an
+ACRN-based application.  This document describes these option settings.
+
+.. contents::
+   :local:
+   :depth: 2
+
+Common option value types
+*************************
+
+Within this option documentation, we refer to some common type
+definitions:
+
+Boolean
+  A true or false value specified as either ``y`` or ``n``. Other
+  values such as ``t`` or ``f`` are not supported.
+
+Hexadecimal
+  A base-16 (integer) value represented by a leading ``0x`` or ``0X`` followed by
+  one or more characters ``0`` to ``9``, ``a`` to ``f``, or ``A`` to ``F``.
+
+Integer
+  A base-10 value represented by the characters ``0`` to ``9``.  The
+  first character must not be a ``0``. Only positive values are
+  expected.
+
+String
+  A sequence of UTF-8 characters.  String-length limits or specific
+  string value restrictions are defined in the option description.
+
+
+.. comment This configdoc.txt is generated during the doc build process
+   from the acrn config schema files found in misc/config_tools/schema
+
+.. include:: configdoc.txt