ocfs2/dlm: Hard code the values for enums

In o2dlm, the enumerated message values are part of the protocol.
The patch hard codes each value so as to reduce the chance of an editing
error causing a protocol mismatch.

Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>