docs: add QAPI namespace "QMP" to qemu-qmp-ref

This also creates the qapi-qmp-index.html index and cross-reference
target.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-ID: <20250313044312.189276-10-jsnow@redhat.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>

docs/conf.py

@@ -163,7 +163,9 @@
 
 # Due to a limitation in Sphinx, we need to know which indices to
 # generate in advance. Adding a namespace here allows that generation.
-qapi_namespaces = set()
+qapi_namespaces = {
+    "QMP",
+}
 
 # -- Options for HTML output ----------------------------------------------
 

docs/interop/qemu-qmp-ref.rst

@@ -8,3 +8,4 @@ QEMU QMP Reference Manual
 
 .. qapi-doc:: qapi/qapi-schema.json
    :transmogrify:
+   :namespace: QMP

qapi/qapi-schema.json

@@ -5,7 +5,7 @@
 #
 # This document describes all commands currently supported by QMP.
 #
-# For locating a particular item, please see the `qapi-index`.
+# For locating a particular item, please see the `qapi-qmp-index`.
 #
 # Most of the time their usage is exactly the same as in the user
 # Monitor, this means that any other document which also describe