plugin: add dump modes to smdb_dump parameter

Dump modes that are available are:

 - 1 : BINARY MODE
 - 2 : DEBUG MODE
 - 3 : HUMAN READABLE MODE

Dump modes were added for verification purposes.

Signed-off-by: Ilya Nelkenbaum <ilyan@mellanox.com>
Signed-off-by: Hal Rosenstock <hal@mellanox.com>