firmware: stratix10-svc: Generic Mailbox Command

Add generic mailbox command that can support SDM command. User can use this
command to send SDM mailbox command. User have to specified an input file
which contain the command data and an output file for SDM response to be
copied over.

Signed-off-by: Teh Wen Ping <wen.ping.teh@intel.com>
Signed-off-by: Kah Jing Lee <kah.jing.lee@intel.com>
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
Link: https://lore.kernel.org/r/20230727192907.982070-1-dinguyen@kernel.org


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>