netfilter: nft_set_rbtree: overlap detection with element re-addition after deletion

netfilter: nft_set_rbtree: overlap detection with element re-addition after deletion

This patch fixes spurious EEXIST errors.

Extend 6dce4a781fa8 ("netfilter: nft_set_rbtree: handle element
re-addition after deletion") to deal with elements with same end flags
in the same transation.

Reset the overlap flag as described by 4392e5177e05 ("netfilter:
nft_set_rbtree: Detect partial overlaps on insertion").

Fixes: 4392e5177e05 ("netfilter: nft_set_rbtree: Detect partial overlaps on insertion")
Fixes: 6dce4a781fa8 ("netfilter: nft_set_rbtree: handle element re-addition after deletion")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>