gapil/compiler/plugins/encoder: Add more debug messages
gapil/compiler/plugins/encoder: Add more debug messages

Not enabled, just helpful when they are enabled.

pmuetschard/gapid,google/gapid,google/gapid,Qining/gapid,google/agi,Qining/gapid,google/gapid,Qining/gapid,Qining/gapid,google/agi,google/agi,google/gapid,Qining/gapid,Qining/gapid,pmuetschard/gapid,google/agi,Qining/gapid,pmuetschard/gapid,google/agi,google/gapid,google/agi,google/gapid,pmuetschard/gapid,pmuetschard/gapid,Qining/gapid,google/agi,google/gapid,pmuetschard/gapid,pmuetschard/gapid,google/agi,pmuetschard/gapid,google/gapid