console/ast2400: Fix swapped address/value writes in writeSIOReg
console/ast2400: Fix swapped address/value writes in writeSIOReg

We need to write the address to 0x2e, and the data to 0x2f.

Change-Id: I1271a134c19d921fa1ee54b5f0d1c0e092df9e2b
Signed-off-by: Jeremy Kerr <68a658b44bbaefab3ef5cd231967195fc0ff9d69@ozlabs.org>
Reviewed-on: http://gfw160.aus.stglabs.ibm.com:8080/gerrit/19146
Tested-by: Jenkins Server
Reviewed-by: A. Patrick Williams III <c87e37b1a4035affd737b461af89fb722d635f4d@us.ibm.com>

open-power/hostboot,csmart/hostboot,alvintpwang/hostboot,csmart/hostboot,open-power/hostboot,alvintpwang/hostboot,Over-enthusiastic/hostboot,alvintpwang/hostboot,csmart/hostboot,open-power/hostboot,Over-enthusiastic/hostboot,open-power/hostboot,Over-enthusiastic/hostboot,alvintpwang/hostboot,open-power/hostboot,csmart/hostboot,Over-enthusiastic/hostboot,alvintpwang/hostboot,Over-enthusiastic/hostboot,csmart/hostboot