kernel-dev,ref-manual: fix old override syntax

Additionally use more common syntax to indicate that an actual machine name is
supposed to be filled in for a concrete use case as has been suggested by Peter
Kjellerstedt (and particularly no KMACHINE). Furthermore add missing quotes in
the reference manual.

Suggested-by: Peter Kjellerstedt <peter.kjellerstedt@axis.com>
(From yocto-docs rev: b66c035970f860b65cf712285f2d5a023620e6c3)

Signed-off-by: Ulrich Ölmann <u.oelmann@pengutronix.de>
Reviewed-by: Quentin Schulz <foss+yocto@0leil.net>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/documentation/ref-manual/variables.rst b/documentation/ref-manual/variables.rst
index a36c4c6df9..54da54f71d 100644
--- a/documentation/ref-manual/variables.rst
+++ b/documentation/ref-manual/variables.rst
@@ -4275,7 +4275,7 @@ system and gives an overview of their function and contents.
       To use the variable, set it in the append file for your kernel recipe
       using the following form::
 
-         KBUILD_DEFCONFIG_KMACHINE ?= defconfig_file
+         KBUILD_DEFCONFIG:<machine> ?= "defconfig_file"
 
       Here is an example from a "raspberrypi2" :term:`KMACHINE` build that uses
       a ``defconfig`` file named "bcm2709_defconfig"::