[docs] Add missing 4.4.0 index
diff --git a/docs/harfbuzz-docs.xml b/docs/harfbuzz-docs.xml
index 0c5e582..00a198a 100644
--- a/docs/harfbuzz-docs.xml
+++ b/docs/harfbuzz-docs.xml
@@ -117,6 +117,7 @@
       <index id="api-index-full"><title>API Index</title><xi:include href="xml/api-index-full.xml"><xi:fallback /></xi:include></index>
       <index id="deprecated-api-index" role="deprecated"><title>Index of deprecated API</title><xi:include href="xml/api-index-deprecated.xml"><xi:fallback /></xi:include></index>
 
+      <index id="api-index-4-4-0" role="4.4.0"><title>Index of new symbols in 4.4.0</title><xi:include href="xml/api-index-4.4.0.xml"><xi:fallback /></xi:include></index>
       <index id="api-index-4-3-0" role="4.3.0"><title>Index of new symbols in 4.3.0</title><xi:include href="xml/api-index-4.3.0.xml"><xi:fallback /></xi:include></index>
       <index id="api-index-4-2-0" role="4.2.0"><title>Index of new symbols in 4.2.0</title><xi:include href="xml/api-index-4.2.0.xml"><xi:fallback /></xi:include></index>
       <index id="api-index-4-1-0" role="4.1.0"><title>Index of new symbols in 4.1.0</title><xi:include href="xml/api-index-4.1.0.xml"><xi:fallback /></xi:include></index>