fix bug in gpu default memory allocating policy (#6268)
fix bug in gpu default memory allocating policy (#6268)


baidu/Paddle,jacquesqiao/Paddle,jacquesqiao/Paddle,luotao1/Paddle,putcn/Paddle,tensor-tang/Paddle,pkuyym/Paddle,PaddlePaddle/Paddle,jacquesqiao/Paddle,putcn/Paddle,QiJune/Paddle,reyoung/Paddle,tensor-tang/Paddle,luotao1/Paddle,luotao1/Paddle,Canpio/Paddle,Canpio/Paddle,jacquesqiao/Paddle,lcy-seso/Paddle,jacquesqiao/Paddle,chengduoZH/Paddle,chengduoZH/Paddle,luotao1/Paddle,lcy-seso/Paddle,baidu/Paddle,chengduoZH/Paddle,QiJune/Paddle,PaddlePaddle/Paddle,tensor-tang/Paddle,baidu/Paddle,putcn/Paddle,PaddlePaddle/Paddle,QiJune/Paddle,putcn/Paddle,lcy-seso/Paddle,luotao1/Paddle,luotao1/Paddle,chengduoZH/Paddle,PaddlePaddle/Paddle,lcy-seso/Paddle,tensor-tang/Paddle,pkuyym/Paddle,Canpio/Paddle,PaddlePaddle/Paddle,tensor-tang/Paddle,putcn/Paddle,PaddlePaddle/Paddle,baidu/Paddle,PaddlePaddle/Paddle,pkuyym/Paddle,QiJune/Paddle,reyoung/Paddle,lcy-seso/Paddle,putcn/Paddle,QiJune/Paddle,QiJune/Paddle,luotao1/Paddle,pkuyym/Paddle,chengduoZH/Paddle,Canpio/Paddle,reyoung/Paddle,Canpio/Paddle,lcy-seso/Paddle,Canpio/Paddle,reyoung/Paddle,Canpio/Paddle,pkuyym/Paddle,jacquesqiao/Paddle,baidu/Paddle,reyoung/Paddle,pkuyym/Paddle,reyoung/Paddle,Canpio/Paddle