kernel-dev/common.rst: fix the in-tree defconfig description

The description of the relation between KBUILD_DEFCONFIG and
SRC_URI is reversed. In fact it is the SRC_URI provided
defconfig which will be dropped by the kernel-yocto class
if both are provided.

(From yocto-docs rev: a808420655a0976ba08f013f468cf80f379b1d89)

Signed-off-by: Adam Blank <adam.blank.g@gmail.com>
Signed-off-by: Antonin Godard <antonin.godard@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

documentation/kernel-dev/common.rst

@@ -650,13 +650,9 @@ the Broadcom 2708/2709 chipset::
 
    KBUILD_DEFCONFIG:raspberrypi2 ?= "bcm2709_defconfig"
 
-Aside from modifying your kernel recipe and providing your own
-``defconfig`` file, you need to be sure no files or statements set
-:term:`SRC_URI` to use a ``defconfig`` other than your "in-tree" file (e.g.
-a kernel's ``linux-``\ `machine`\ ``.inc`` file). In other words, if the
-build system detects a statement that identifies an "out-of-tree"
-``defconfig`` file, that statement will override your
-:term:`KBUILD_DEFCONFIG` variable.
+If the build system detects a statement that identifies an "out-of-tree"
+``defconfig`` file, your :term:`KBUILD_DEFCONFIG` variable will take precedence
+over it.
 
 See the
 :term:`KBUILD_DEFCONFIG`