dataplacement: increase max data placement IDs to 128

dataplacement: increase max data placement IDs to 128

Some users have requested the ability to test a larger number of
placement IDs in a single job. Bump the max placement IDs to 128.
Change the type to 16 bits to reduce the amount of space these
additional IDs will consume.

Also bump the server version for this change.

Signed-off-by: Vincent Fu <vincent.fu@samsung.com>