[OE-core] [PATCH] meta/lib/oe/rootfs.py: clean up dnf cache after creating an image

[Alexander Kanavin]

It contains cached metadata for a transient repository that is used
only when creating images on the host, and so is of no use on target
images. Dnf will recreate the cache on target when needed.

Signed-off-by: Alexander Kanavin <alexander.kanavin at linux.intel.com>
---
 meta/lib/oe/rootfs.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/meta/lib/oe/rootfs.py b/meta/lib/oe/rootfs.py
index 9d4727e76c1..71bd1a78dce 100644
--- a/meta/lib/oe/rootfs.py
+++ b/meta/lib/oe/rootfs.py
@@ -525,7 +525,8 @@ class RpmRootfs(Rootfs):
             self.pm.save_rpmpostinst(pkg)
 
     def _cleanup(self):
-        pass
+        self.pm._invoke_dnf(["clean", "all"])
+
 
 class DpkgOpkgRootfs(Rootfs):
     def __init__(self, d, progress_reporter=None, logcatcher=None):
-- 
2.14.1