sata, highbank: fix ordering of SGPIO signals

The ACTIVITY and ERROR signals were reversed in the original commit.
Fix that so that hard drive activity does not show up on the error
light, and attempts to indicate that the hard drive is failing do
not show up as hard drive activity. This fixes a fairly serious
functional bug in the driver, but failing to apply this patch will
not cause any stability issues on the system.

Signed-off-by: Mark Langsdorf <mark.langsdorf@calxeda.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org