ocfs2/dlm: dlm_is_lockres_migrateable() returns boolean

Patch cleans up the gunk added by commit 388c4bcb

.
dlm_is_lockres_migrateable() now returns 1 if lockresource is deemed
migrateable and 0 if not.

Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Joel Becker <jlbec@evilplan.org>