use p instead of i in roi_average_align_2d
use p instead of i in roi_average_align_2d

hvy/chainer,okuta/chainer,niboshi/chainer,keisuke-umezawa/chainer,hvy/chainer,wkentaro/chainer,pfnet/chainer,tkerola/chainer,chainer/chainer,okuta/chainer,okuta/chainer,hvy/chainer,keisuke-umezawa/chainer,niboshi/chainer,hvy/chainer,niboshi/chainer,okuta/chainer,wkentaro/chainer,chainer/chainer,chainer/chainer,wkentaro/chainer,chainer/chainer,niboshi/chainer,keisuke-umezawa/chainer,keisuke-umezawa/chainer,wkentaro/chainer