Update nmod-poss.md
Update nmod-poss.md

FinnTreeBank not use nmod:poss (but nmod)
fginter/docs-fginterfork,UniversalDependencies/docs,UniversalDependencies/docs,fginter/docs-fginterfork,fginter/docs,PhyloStar/UDTelugu,PhyloStar/UDTelugu,fginter/docs,fginter/docs-fginterfork,fginter/docs-fginterfork,fginter/docs,UniversalDependencies/docs,fginter/docs,PhyloStar/UDTelugu,PhyloStar/UDTelugu,UniversalDependencies/docs,PhyloStar/UDTelugu,UniversalDependencies/docs,fginter/docs,PhyloStar/UDTelugu,UniversalDependencies/docs,fginter/docs-fginterfork