Don't reopen device files
Don't reopen device files

Move open() and close() calls into ...init() and ...release() where they belong

jquesnelle/libntru,jl777/libntru,jl777/libntru,iblumenfeld/libntru,iblumenfeld/libntru,jl777/libntru,jquesnelle/libntru,jquesnelle/libntru,iblumenfeld/libntru