Add forgotten argument to xi*/xo* functions

dotfiles/bash/main.bashrc

     # Common clipboard operations with fixnl() on top
     #
     local op=$1
+    local file=${2:-/dev/stdin}
     case $op in
         oo) xclip -selection clipboard -o    | fixnl ;;
         o)  xclip -o                         | fixnl ;;
         ii) fixnl -c | xclip -selection clipboard -i ;;
         i)  fixnl -c | xclip -i                      ;;
-    esac
+    esac <"$file"
 }
 
 xod() {