user/tmux: restore xterm-DECLRMM.patch
This patch will be needed until >= 3.0. https://github.com/tmux/tmux/commit/26f274011096b9eacfd2753d8f7afcb63e796ab9
This patch will be needed until >= 3.0. https://github.com/tmux/tmux/commit/26f274011096b9eacfd2753d8f7afcb63e796ab9