The vim-common-5.7-6 package creates a link from /usr/share/vim/vim57/macros/gvimrc to /usr/share/vim/vim57/macros/vimrc. However, vim always reads the system vimrc at startup then goes on to read the system gvimrc if it is there, so there is no need to create the link. It doesn't seem to create any problems that I can see but it is unnecessary.
Changed in 6.0-0.21