[PATCH v2 3/4] doc: bitbake-user-manual-metadata: explain inherit_defer example

Add a short paragraph describing how the inherit_defer makes use of override
syntax to achieve conditional inheritance, and rename VARIABLE to
VARNAME so the example uses the same identifier as the preceding
code block.

Signed-off-by: Dawid Bijak <[email protected]>
---
 doc/bitbake-user-manual/bitbake-user-manual-metadata.rst | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/doc/bitbake-user-manual/bitbake-user-manual-metadata.rst b/doc/bitbake-user-manual/bitbake-user-manual-metadata.rst
index b886e0578..0c7c3ff99 100644
--- a/doc/bitbake-user-manual/bitbake-user-manual-metadata.rst
+++ b/doc/bitbake-user-manual/bitbake-user-manual-metadata.rst
@@ -832,8 +832,13 @@ Here is an example::
 One way to achieve a conditional inherit in this case is to use
 overrides::
 
-   VARIABLE = ""
-   VARIABLE:someoverride = "myclass"
+   VARNAME = ""
+   VARNAME:someoverride = "myclass"
+
+:ref:`inherit_defer <ref-bitbake-user-manual-metadata-inherit-defer>`
+defers the evaluation of ``${VARNAME}`` until the end of
+parsing. Assuming ``someoverride`` is in :term:`OVERRIDES`, ``${VARNAME}``
+expands to ``myclass``, which is then inherited.
 
 Alternatively, you could use an inline Python expression in the
 following form::
-- 
2.48.1