[PATCH V4] kbuild: Add rule to build .dt.yaml files for overlays

[Viresh Kumar]

The overlay source files are named with .dtso extension now, add a new
rule to generate .dt.yaml for them.

Reviewed-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
Tested-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
---
V4:
- Rebase over Frank's cleanup patch:

  https://lore.kernel.org/lkml/20210324223713.1334666-1-frowand.list@xxxxxxxxx/

- Drop changes to drivers/of/unittest-data/Makefile.
- Drop modifications to the rule that builds .dtbo files (as it is
  already updated by Frank).

 scripts/Makefile.lib | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index 814b430b407e..a682869d8f4b 100644
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -376,6 +376,9 @@ endef
 $(obj)/%.dt.yaml: $(src)/%.dts $(DTC) $(DT_TMP_SCHEMA) FORCE
 	$(call if_changed_rule,dtc,yaml)
 
+$(obj)/%.dt.yaml: $(src)/%.dtso $(DTC) $(DT_TMP_SCHEMA) FORCE
+	$(call if_changed_rule,dtc,yaml)
+
 dtc-tmp = $(subst $(comma),_,$(dot-target).dts.tmp)
 
 # Bzip2
-- 
2.25.0.rc1.19.g042ed3e048af