git-rebase: Use --ignore-if-in-upstream option when executing git-format-patch.
git-rebase: Use --ignore-if-in-upstream option when executing git-format-patch.

This reduces the number of conflicts when rebasing after a series of
patches to the same piece of code is committed upstream.

Signed-off-by: Robert Shearman <7e09c9d3e96378bf549fc283fd6e1e5b7014cc33@codeweavers.com>
Signed-off-by: Junio C Hamano <dc50d1021234060e53ec42a77d526afa2fe07479@cox.net>

destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git