Merge branch 'jn/unpack-trees-checkout-m-carry-deletion' into maint

* jn/unpack-trees-checkout-m-carry-deletion:
checkout -m: attempt merge when deletion of path was staged
unpack-trees: use 'cuddled' style for if-else cascade
unpack-trees: simplify 'all other failures' case

diff --cc unpack-trees.c
Simple merge