Add zstd based io decompression.
Based largely on the existing xzio, implement the same features using
the zstd library already included in the project.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Avnish Chouhan <avnish@linux.ibm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>