[wesnoth-commits] [wesnoth/wesnoth] 323ce6: Show id in "skipping duplicate variation" warning

[Steve Cotton]

  Branch: refs/heads/master
  Home:   https://github.com/wesnoth/wesnoth
  Commit: 323ce6ec260f29f81c4cb4a703cc2202610db982
      https://github.com/wesnoth/wesnoth/commit/323ce6ec260f29f81c4cb4a703cc2202610db982
  Author: Steve Cotton <steve at octalot.co.uk>
  Date:   2021-11-12 (Fri, 12 Nov 2021)

  Changed paths:
    M src/units/types.cpp

  Log Message:
  -----------
  Show id in "skipping duplicate variation" warning

Add a useful identifier to the message

    error config: Skipping duplicate unit variation ID: ''

This warning is generally shown because the variation_id is completely
missing, and so the message appeared as above, without any hint of which
unit was causing the problem.

In contrast to 19a5ce83's warning, this one is printed multiple times to
stdout even if the messages are identical; therefore backporting this to
1.16 seems reasonable.