Don't do anything when xcp() is run without arguments

dotfiles/config/bashum/main.bashrc

@@ -633,6 +633,7 @@ xcp() {
     # Copy paths of $@ to clipboard
     #
     local path
+    test $# -gt 0 || return 0
     find "$@" -maxdepth 0 -mindepth 0 \
       | while read -r path; do
             readlink -e "$path"