staging: unisys: visorhba: Remove unused MAX_BUF define

Remove the MAX_BUF define and associated comments.

Signed-off-by: Bryan Thompson <bryan.thompson@unisys.com>
Reviewed-by: Tim Sell <Timothy.Sell@unisys.com>
Signed-off-by: David Kershner <david.kershner@unisys.com>
Reviewed-by: David Binder <david.binder@unisys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>