ram_pcd_message: pass libff::bit_vector by const reference to avoid copies#224

MozirDmitriy wants to merge 2 commits intoscipr-lab:masterscipr-lab/libsnark:masterfrom

MozirDmitriy:fix/ram-pcd-message-bitvector-const-refMozirDmitriy/libsnark:fix/ram-pcd-message-bitvector-const-refCopy head branch name to clipboard