ls-tree: `-l` should not imply recursive listing
In
9c4d58ff2c (ls-tree: split up "fast path" callbacks, 2022-03-23), a
refactoring of the various read_tree_at() callbacks caused us to
unconditionally recurse into directories if `-l` (long format) was
passed on the command line, regardless of whether or not we also pass
the `-r` (recursive) flag.
Fix this by making show_tree_long() return the value of `recurse`,
rather than always returning 1. This value is interpreted by
read_tree_at() to be a signal on whether or not to recurse.
Signed-off-by: Josh Steadmon <steadmon@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>