Fix 2 small issues in DCE
Fix 2 small issues in DCE

We may kill off VkQueueSubmit, if the only thing they do is
signal a fence.

We may also kill off pipelineLayouts if they are only used to
update push constants.

google/gapid,google/agi,Qining/gapid,pmuetschard/gapid,dsrbecky/gapid,baldwinn860/gapid,google/agi,baldwinn860/gapid,google/gapid,google/agi,google/gapid,pmuetschard/gapid,baldwinn860/gapid,dsrbecky/gapid,Qining/gapid,dsrbecky/gapid,baldwinn860/gapid,dsrbecky/gapid,google/agi,pmuetschard/gapid,pmuetschard/gapid,Qining/gapid,google/gapid,google/agi,baldwinn860/gapid,google/gapid,google/agi,google/agi,google/gapid,Qining/gapid,google/agi,pmuetschard/gapid,google/gapid,Qining/gapid,pmuetschard/gapid,pmuetschard/gapid,baldwinn860/gapid,baldwinn860/gapid,dsrbecky/gapid,pmuetschard/gapid,dsrbecky/gapid,dsrbecky/gapid,Qining/gapid,dsrbecky/gapid,Qining/gapid,baldwinn860/gapid,Qining/gapid,google/gapid