keymaster: ta: set max message version to 3
The max message version inform keymaster what request/response the TA can support for a given crypto operation.
Following the message version, the expected response can be organized differently.
For example with KM_GENERATE_KEY operation, the output data must contain certificate chain [1] with message version >= 4.
For now we don't support yet all the format of message version 4, instead we should return max message version 3.