The ornamental design for an igniter for barbecue, as shown and described.
1. Igniter for barbecue
1.1 : Unfolded
1.2 : Front view/back view
1.3 : Left
1.4 : Right
1.5 : Folded side view
1.6 : Folded front view
1.7 : Folded top view
The design represents an igniter for barbecue made of cardboard; the thin lines represent lines of folding of cardboard; no protection is sought for the features shown in broken lines.