Intellij has "Scroll to Center" bound to Ctrl-M.
Add the Ctrl-L binding in the keymap by going into "Settings | Keymap", choose "Emacs" or make a copy of the default keymap, find the current binding by entering "Scroll to Center" in the search box, double click on the line where the binding is defined, select "Add Keyboard Shortcut", type Ctrl-L key sequence in the "First Stroke" text field and click OK.