[RFT #2] libata (SATA) driver fixes

See attached changelog and patch, for review and testing.

This includes some fixes for some ugly probe-related bugs, rarely hit 
thankfully.  It also includes new "future nvidia SATA" support and 
Promise SATAII TX2/4 support.

Note that this patch changes the interrupt-acknowledgement code in 
sata_promise.c for all Promise controllers, not just the new SATAII 
ones.  This should be safe and indeed desirable, but warrants special 
mention (and testing).

This is going to Linus/Andrew for 2.6.11 real soon now.

	Jeff