[openwrt/openwrt] build,json: fix duplicates in default_packages

[LEDE Commits]

aparcar pushed a commit to openwrt/openwrt.git, branch master:
https://git.openwrt.org/7f4c2b1a4f9216218dced64794318f2197565c85

commit 7f4c2b1a4f9216218dced64794318f2197565c85
Author: Paul Spooren <mail at aparcar.org>
AuthorDate: Sat Mar 20 23:23:34 2021 -1000

    build,json: fix duplicates in default_packages
    
    Calling without the DUMP=1 argument causes the target specific Makefile
    to be "included" again which adds the target specific packages twice,
    once on the actual run and once included from `include/target.mk`.
    
    This led to duplicate package entries, causing confusion in downstream
    projects using the generated JSON files.
    
    While at it, apply `black` style to Python script.
    
    Signed-off-by: Paul Spooren <mail at aparcar.org>
---
 scripts/json_overview_image_info.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/scripts/json_overview_image_info.py b/scripts/json_overview_image_info.py
index ca6fbbc962..23d8dcb857 100755
--- a/scripts/json_overview_image_info.py
+++ b/scripts/json_overview_image_info.py
@@ -38,9 +38,10 @@ if output:
             "make",
             "--no-print-directory",
             "-C",
-            "target/linux/{}".format(output['target'].split('/')[0]),
+            "target/linux/{}".format(output["target"].split("/")[0]),
             "val.DEFAULT_PACKAGES",
             "val.ARCH_PACKAGES",
+            "DUMP=1",
         ],
         stdout=PIPE,
         stderr=PIPE,