[PATCH RFC 1/2] images: allow suppressing missing firmware stderr output

[Ahmad Fatoum <a.fatoum@barebox.org>]

There is a Kconfig option to turn missing firmware to an error, but
there is no way to suppress the warning that is printed in any case.

Suppressing the warning is useful however when reproducing an issue with
a multi_defconfig, so allow changing it to output to stdout by means of
an environment variable.

Signed-off-by: Ahmad Fatoum <a.fatoum@barebox.org>
---
 images/Makefile | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/images/Makefile b/images/Makefile
index ebbf57b46355..96f66b0a8e70 100644
--- a/images/Makefile
+++ b/images/Makefile
@@ -254,7 +254,8 @@ images: $(image-y-path) $(flash-link) $(flash-list) $(symlink-y-path) FORCE
 	@echo "images built:"
 	@for i in $(image-y); do \
 	  if [ -s $(obj)/$$i ]; then echo $$i; \
-	  else >&2 echo "** $$i skipped due to missing firmware **"; \
+	  else $(if $(NO_MISSING_FIRMWARE_WARNING),,>&2) \
+	  	echo "** $$i skipped due to missing firmware **"; \
 	  $(if $(CONFIG_MISSING_FIRMWARE_ERROR), >&2 sed 's/^/\t/' <$(obj)/$${i}.missing-firmware; missing=1;) \
 	  fi; done; if [ -n "$$missing" ]; then \
 	    echo >&2 "Firmware missing in CONFIG_MISSING_FIRMWARE_ERROR=y build"; exit 1; fi
-- 
2.47.3