[meta-lts-mixins][wrynose/linux-firmware][PATCH] drop LTS_LINUX_FIRMWARE_MIXIN_DEFAULT_PREFERENCE and use just DEFAULT_PREFERENCE

This change reverts 7d003ac, 2145371 and 6b8dd8b. The idea with the variable
LTS_LINUX_FIRMWARE_MIXIN_DEFAULT_PREFERENCE was to make it simpler to choose
the version using only one variable, but it ends up being a new variable,
so nobody knows it.

We can do the same using only the DEFAULT_PREFERENCE that already exists
and whose use is known.

Signed-off-by: Jose Quaresma <[email protected]>
---
 README.md                                                | 8 ++++----
 conf/layer.conf                                          | 3 ---
 recipes-kernel/linux-firmware/linux-firmware_20260519.bb | 2 +-
 3 files changed, 5 insertions(+), 8 deletions(-)

diff --git a/README.md b/README.md
index deeca33..ef6f019 100644
--- a/README.md
+++ b/README.md
@@ -10,12 +10,12 @@ linux-firmware recipe from the master branch of openembedded-core.
 
 In order to make this layer Yocto Project Compatible, the layer should not provide
 new versions of packages by default. Because of this, the recipe provided in this
-layer will not be used unless the LTS_LINUX_FIRMWARE_MIXIN_DEFAULT_PREFERENCE
-variable is modified. The default value is:
+layer will not be used unless that is explicitly stated. To use the provided
+linux-firmware recipe, the following can be done:
 
 ```
-# DEFAULT_PREFERENCE for linux-firmware provided by the layer
-LTS_LINUX_FIRMWARE_MIXIN_DEFAULT_PREFERENCE ?= "-1"
+# please use 'DEFAULT_PREFERENCE:your_override = ""' to keep Yocto Project Compatible
+echo 'DEFAULT_PREFERENCE = ""' >> recipes-kernel/linux-firmware/linux-firmware_%.bbappend
 ```
 
 Dependencies
diff --git a/conf/layer.conf b/conf/layer.conf
index 59b9e0c..5e1f7f2 100644
--- a/conf/layer.conf
+++ b/conf/layer.conf
@@ -17,6 +17,3 @@ LAYERDEPENDS_lts-linux-firmware-mixin = " \
 
 # https://git.openembedded.org/openembedded-core/commit/?id=2b75c7ba5e3aa6fc57d7b4afe59e2277b4d87de1
 firmwaredir = "${nonarch_base_libdir}/firmware"
-
-# DEFAULT_PREFERENCE for linux-firmware provided by the layer
-LTS_LINUX_FIRMWARE_MIXIN_DEFAULT_PREFERENCE ?= "-1"
diff --git a/recipes-kernel/linux-firmware/linux-firmware_20260519.bb b/recipes-kernel/linux-firmware/linux-firmware_20260519.bb
index 50df8e9..f2cd873 100644
--- a/recipes-kernel/linux-firmware/linux-firmware_20260519.bb
+++ b/recipes-kernel/linux-firmware/linux-firmware_20260519.bb
@@ -3694,4 +3694,4 @@ INSANE_SKIP:${PN} = "already-stripped"
 SYSROOT_DIRS_IGNORE += "${firmwaredir}"
 
 # Don't prefer it by default
-DEFAULT_PREFERENCE = "${LTS_LINUX_FIRMWARE_MIXIN_DEFAULT_PREFERENCE}"
+DEFAULT_PREFERENCE = "-1"
-- 
2.54.0