adding missing metaschema composition transform. This was removed in …

…the cleanup by accident.

toolchains/xslt-M4/compose/reduce-map.xsl

@@ -0,0 +1,47 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
+    xmlns:xs="http://www.w3.org/2001/XMLSchema"
+    xmlns:math="http://www.w3.org/2005/xpath-functions/math"
+    xmlns="http://csrc.nist.gov/ns/oscal/metaschema/1.0"
+    xpath-default-namespace="http://csrc.nist.gov/ns/oscal/metaschema/1.0"
+    xmlns:html="http://www.w3.org/1999/xhtml"
+
+    exclude-result-prefixes="#all"
+    version="3.0">
+
+    <xsl:mode on-no-match="shallow-copy"/>
+
+    <xsl:template match="@group-name | @group-xml| @link | @root-name | @use-name"/>
+
+    <xsl:template match="formal-name | description | remarks"/>
+
+    <xsl:template match="/map">
+        <model root-at="{*/@root-name}">
+            <xsl:copy-of select="@*"/>
+            <xsl:apply-templates/>
+        </model>
+    </xsl:template>
+
+    <xsl:template match="@name">
+        <xsl:copy-of select="."/>
+        <xsl:if test="empty(../parent::group)">
+            <xsl:attribute name="key" select="(../@root-name,../@use-name,.)[1]"/>
+        </xsl:if>
+        <!--<xsl:if test="not(../@in-xml=('UNWRAPPED','HIDDEN'))">
+            <xsl:attribute name="gi"  select="(../@root-name,../@use-name,.)[1]"/>
+        </xsl:if>-->
+    </xsl:template>
+
+    <xsl:template match="@required"/>
+
+    <xsl:template match="@max-occurs">
+        <!--<xsl:attribute name="occurs" select="(../@min-occurs,.) => string-join(' ')"/>-->
+    </xsl:template>
+
+    <xsl:template match="@min-occurs"/>
+
+    <!--<xsl:template match="@min-occurs[empty(../@max-occurs)]">
+        <xsl:attribute name="occurs" select="(.,'1') => string-join(' ')"/>
+    </xsl:template>-->
+
+</xsl:stylesheet>