filelock: make lease_alloc() take a flags argument

filelock: make lease_alloc() take a flags argument

__break_lease() currently overrides the flc_flags field in the lease
after allocating it. A forthcoming patch will add the ability to request
a FL_DELEG type lease.

Instead of overriding the flags field, add a flags argument to
lease_alloc() and lease_init() so it's set correctly after allocating.

Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: NeilBrown <neil@brown.name>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Link: https://patch.msgid.link/20251111-dir-deleg-ro-v6-1-52f3feebb2f2@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>