mtip32xx: removed the irrelevant argument of mtip_hw_submit_io() and the unused member of struct driver_data

Removed the following:
	* irrelevant argument 'barrier' of mtip_hw_submit_io()
	* unused member 'eh_active' of struct driver_data
Signed-off-by: Asai Thambi S P <asamymuthupa@micron.com>
Signed-off-by: Sam Bradshaw <sbradshaw@micron.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>