securerom: remove hbi_ImageId
securerom: remove hbi_ImageId

Similar to commit 951f02c32769 ("bootloader: Remove hbi_ImageId"), the
ImageId present in the securerom is now munged into the bootloader
as part of the build process resulting in unnecessary SBE updates.

Resolves #121

Signed-off-by: Robert Lippert <c065cdb6ddd7bea176bf96c0c5ae92b2a677c1e0@google.com>
Change-Id: If5623c68e5c89ee23c81bba062b78c1c98028441
Reviewed-on: http://ralgit01.raleigh.ibm.com/gerrit1/48719
Tested-by: Jenkins Server <8e3f934e4c44875bc48d33da3ea13d93ba9a233f@us.ibm.com>
Tested-by: Jenkins OP Build CI <e610bd72261d3c0a48f1e8ae36832ab00774d426@us.ibm.com>
Tested-by: Jenkins OP HW <0eb0fff262f74a65a832afbcc7b153e391c9a3fd@us.ibm.com>
Tested-by: FSP CI Jenkins <aa9e4d9ac7cd25905e9c0dd36d4150516e73dd86@us.ibm.com>
Reviewed-by: Nicholas E. Bofferding <fb8db48116bc8a69e29dd8cdb037246f232f4af5@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