OvmfPkg/MptScsiDxe: Initialize hardware

OvmfPkg/MptScsiDxe: Initialize hardware

Reset and send the IO controller initialization request. The reply is
read back to complete the doorbell function but it isn't useful to us
because it doesn't contain relevant data or status codes.

See "LSI53C1030 PCI-X to Dual Channel Ultra320 SCSI Multifunction
Controller" technical manual for more information.

Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=2390
Signed-off-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
Message-Id: <20200504210607.144434-11-nikita.leshchenko@oracle.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>