x86: Concurrent FPDMA READ/WRITE QUEUED Under SATA Module

Starting with this release, concurrent READ/WRITE FPDMA QUEUED commands are supported. There is considerable performance enhancement when performing I/O operations using the Solaris marvell88sx driver under specific workload conditions. Other workloads benefit to a smaller degree. There is also significant performance enhancement under many workloads for drives that support this optional portion of the SATA specification.