ksmbd: set epoch in create context v2 lease

[ Upstream commit d045850b ]

To support v2 lease(directory lease), ksmbd set epoch in create context
v2 lease response.

Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>