ksmbd: don't increment epoch if current state and request state are same

[ Upstream commit b6e9a44e ]

If existing lease state and request state are same, don't increment
epoch in create context.

Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>