When MMIO i/o errors to the OCMBs are found switch to using SBE scoms
When MMIO i/o errors to the OCMBs are found switch to using SBE scoms

Previously we would switch over to doing i2c scoms from the host
in when we found i/o ops but there is a security option that can
disable this path. In order to have a safe and consistent backup
when MMIO fails we will always fall back to asking the SBE to
perform the i2c scoms to the OCMB with a PSU op instead of doing
the i2c scom from the host.

Change-Id: I3dde410c314e84d97a4390bb95052618eb7a4b0f
RTC: 195684
Reviewed-on: http://rchgit01.rchland.ibm.com/gerrit1/107544
Reviewed-by: Matt Derksen <7e9f2fc2ed13c4ee3c2ab17f188630a0f557de86@us.ibm.com>
Reviewed-by: Deborah L McLemore <1938e6bc52a6fb400ff401d42bc5360c2c7aaa30@us.ibm.com>
Tested-by: Jenkins Server <8e3f934e4c44875bc48d33da3ea13d93ba9a233f@us.ibm.com>
Tested-by: Jenkins OP Build CI <e610bd72261d3c0a48f1e8ae36832ab00774d426@us.ibm.com>
Tested-by: Jenkins Combined Simics CI <8312af3886dfc9bb930f549023677220805b137e@us.ibm.com>
Tested-by: FSP CI Jenkins <aa9e4d9ac7cd25905e9c0dd36d4150516e73dd86@us.ibm.com>
Tested-by: Jenkins OP HW <0eb0fff262f74a65a832afbcc7b153e391c9a3fd@us.ibm.com>
Tested-by: Hostboot CI <52521565bd8ea18a2b112942dce4f4220a97c2c8@us.ibm.com>
Reviewed-by: Daniel M Crowell <912029ca9254ac7b5854e56910561d682e1fa2d0@us.ibm.com>

open-power/hostboot,open-power/hostboot,open-power/hostboot,open-power/hostboot,open-power/hostboot