Add `chassis bootmbox` command to set and get Boot Initiator Mailbox
boot parameter (id 7) the easy way. The command allows for getting
and setting the data both in hex and text modes, as well as properly
decodes IANA Enterprise number for block 0. It can get/set the whole
mailbox at once or operate on separate data blocks.
This commit enhances the chassis_get_boot_param() function with extra
arguments to re-use its code in handling of the added command.
Documentation update will follow.
Signed-off-by: Alexander Amelkin <alexander@amelkin.msk.ru>
62a04390e1