dev-manual: fix testimage usage instructions

The proper way to inherit the testimage class is now

IMAGE_CLASSES += "testimage"

so change lines with 'INHERIT += "testimage"' to match. This makes the
dev-manual consistent with the migration guide, which already specifies
that the old way causes an error.

(From yocto-docs rev: 4d660551a6547ffe216e53402759baef424c4da2)

Signed-off-by: Trevor Gamblin <tgamblin@baylibre.com>
Reviewed-by: Michael Opdenacker <michael.opdenacker@bootlin.com>
Signed-off-by: Steve Sakoman <steve@sakoman.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/documentation/dev-manual/upgrading-recipes.rst b/documentation/dev-manual/upgrading-recipes.rst
index 13133fddcf..33a7ca39dd 100644
--- a/documentation/dev-manual/upgrading-recipes.rst
+++ b/documentation/dev-manual/upgrading-recipes.rst
@@ -117,7 +117,7 @@ The following steps describe how to set up the AUH utility:
       class, which is optional, you need to have the following set in
       your ``conf/local.conf`` file::
 
-         INHERIT += "testimage"
+         IMAGE_CLASSES += "testimage"
 
       .. note::