xml: Slight change in VPR XML format.

Support a format for pb_type which doesn't require repeating the name
many times. Use the xmlsort style sheet to generate the old XML version.

The changes are;
 * Remove the requirement to give an interconnect a name.
 * Moving from attributes for input/output to "port" tags.
 * Decompose the old 'PB_TYPE.PORT[BIT]' into attributes on "port" tag.
 * "Port" tags have a 'from' attribute. If left blank it defaults to the
   current pb_type.

Before;
```xml
<direct input="XXXX.CLOCK_ENABLE" output="in_cen.EN" name="XXXX">
```

After;
```xml
<direct>
  <port name="CLOCK_ENABLE" type="input"/>
  <port name="EN" type="output" from="in_cen"/>
</direct>
```

Disadvantages:
 * This is more verbose.

Advantages:
 * The 'default to current pb_type' means that you can do;
```xml
<pb_type name="tristate" num_pb="1">
  <xi:include href="../tri/io_tri.pb_type.xml" xpointer="xpointer(pb_type/child::node())"/>
</pb_type>
```

Signed-off-by: Tim 'mithro' Ansell <me@mith.ro>

xmlsort.xsl

diff --git a/xmlsort.xsl b/xmlsort.xsl
index b61d473..49c1749 100644
--- a/xmlsort.xsl
+++ b/xmlsort.xsl
@@ -12,13 +12,57 @@
     <xsl:copy>
       <!-- Sort the attributes by name and remove the xml:base attribute -->
       <xsl:for-each select="@*[name()!='xml:base']">
-        <xsl:sort select="name( . )"/>
-        <xsl:attribute name="{local-name()}"><xsl:value-of select="normalize-space(.)"/></xsl:attribute>
+	<xsl:sort select="name( . )"/>
+	<xsl:attribute name="{local-name()}"><xsl:value-of select="normalize-space(.)"/></xsl:attribute>
       </xsl:for-each>
       <xsl:apply-templates/>
     </xsl:copy>
   </xsl:template>
 
+  <!-- Allow from attribute which gives you a relative to a given pb_type -->
+  <xsl:template name="from-pb_type">
+    <xsl:choose>
+      <xsl:when test="@from='current'"><xsl:value-of select="ancestor::pb_type[1]/@name"/></xsl:when>
+      <xsl:when test="@from"><xsl:value-of select="@from"/></xsl:when>
+      <xsl:otherwise><xsl:value-of select="ancestor::pb_type[1]/@name"/></xsl:otherwise>
+    </xsl:choose>
+  </xsl:template>
+
+  <!--
+    Convert
+     * <port name=XXX> 				to XXX
+     * <port name=XXX bit=Y> 			to XXX[Y]
+     * <port name=XXX bit_msb=M bit_lsb=L>	to XXX[M:L]
+    -->
+  <xsl:template name="port-value"><xsl:value-of select="@name"/><xsl:choose><xsl:when test="@bit">[<xsl:value-of select="@bit"/>]</xsl:when><xsl:when test="@bit-msb">[<xsl:value-of select="@bit-msb"/>:<xsl:value-of select="@bit-lsb"/>]</xsl:when><xsl:otherwise></xsl:otherwise></xsl:choose></xsl:template>
+
+  <!--
+    Convert
+      <interconnect><XXX><port type='input' ...><port type='output' ...></XXX><YYY../></interconnect>
+    to
+      <interconnect><XXX input='...' output='...'><YYY../></XXX></interconnect>
+    -->
+  <xsl:template match="interconnect/*/port[@type='input']">
+    <xsl:attribute name="input"><xsl:call-template name="from-pb_type"/>.<xsl:call-template name="port-value"/></xsl:attribute>
+  </xsl:template>
+  <xsl:template match="interconnect/*/port[@type='output']">
+    <xsl:attribute name="name"><xsl:call-template name="from-pb_type"/>-<xsl:call-template name="port-value"/></xsl:attribute>
+    <xsl:attribute name="output"><xsl:call-template name="from-pb_type"/>.<xsl:call-template name="port-value"/></xsl:attribute>
+  </xsl:template>
+  <!--
+    Convert
+      <loc ...><port ...><port ...></loc>
+    to
+      <loc ...>BLOCK.PORT BLOCK.PORT</loc>
+    -->
+  <xsl:template match="loc/port"><xsl:text>
+      </xsl:text><xsl:call-template name="from-pb_type"/>.<xsl:call-template name="port-value"/>
+  </xsl:template>
+  <xsl:template match="loc/port[last()]"><xsl:text>
+      </xsl:text><xsl:call-template name="from-pb_type"/>.<xsl:call-template name="port-value"/><xsl:text>
+    </xsl:text>
+  </xsl:template>
+
   <!-- Remove duplicate model nodes -->
   <xsl:key name="model-by-name" match="model" use="@name" />
   <xsl:template match="models">