[PATCH] sata_mv: deal with interrupt coalescing interrupts

In some systems, it is possible that the BIOS may have enabled interrupt coalescing
for the Marvell controllers which support it.  This patch adds code to detect/ack
interrupts from the chip's coalescing (combing) logic.

Signed-off-by: Mark Lord <liml@rtr.ca>
Signed-off-by: Jeff Garzik <jeff@garzik.org>