stage0:  remove superfluous %v Printf verb from logged message when tree cache is bad
stage0:  remove superfluous %v Printf verb from logged message when tree cache is bad

Fixes #2749

sstabellini/rkt,Shashwatsh/rkt,dgonyeo/rkt,mike1729/rkt,s-urbaniak/rkt,shobhit85/rkt,yifan-gu/rocket,intelsdi-x/rkt,Shashwatsh/rkt,dgonyeo/rkt,yifan-gu/rocket,jakon89/rkt,nhlfr/rkt,cab105/rkt,lucasallan/rkt,monstermunchkin/rkt,yifan-gu/rkt,matthaias/rkt,alban/rkt,kinvolk/rkt,coreos/rkt,rkt/rkt,jonboulle/rkt,jonboulle/rkt,alban/rkt,sgotti/rkt,sgotti/rkt,alban/rkt,achanda/rkt,mike1729/rkt,akshaykarle/rkt,mike1729/rkt,lucasallan/rkt,kinvolk/rkt,cab105/rkt,yifan-gu/rkt,s-urbaniak/rkt,matthaias/rkt,jakon89/rkt,squeed/rkt,euank/rkt,nhlfr/rkt,intelsdi-x/rkt,ybubnov/rkt,Wilybald/rkt,s-urbaniak/rkt,joshix/rkt,monstermunchkin/rkt,achanda/rkt,tmrts/rkt,Wilybald/rkt,akshaykarle/rkt,akshaykarle/rkt,Wilybald/rkt,kinvolk/rkt,rkt/rkt,jonboulle/rkt,joshix/rkt,Wilybald/rkt,sstabellini/rkt,joshix/rkt,intelsdi-x/rkt,tmrts/rkt,sgotti/rkt,cab105/rkt,ybubnov/rkt,euank/rkt,matthaias/rkt,monstermunchkin/rkt,shobhit85/rkt,squeed/rkt,rkt/rkt,achanda/rkt,euank/rkt,nhlfr/rkt,yifan-gu/rkt,jjlakis/rkt,yifan-gu/rocket,lucasallan/rkt,lucasallan/rkt,squeed/rkt,tmrts/rkt,coreos/rkt,kinvolk/rkt,joshix/rkt,jjlakis/rkt,dgonyeo/rkt,shobhit85/rkt,coreos/rkt,ybubnov/rkt,jakon89/rkt,sstabellini/rkt,rkt/rkt,jjlakis/rkt,Shashwatsh/rkt