* third-party lib offline compilation support for mkldnn flashattn and gtest

* fix bug

* ignore dirty

* Reorganize the forward codes of flash-attention.

* Fix forward.

* Remove some noused codes.

* Simplify codes and fix backward.

* Change all LOG(INFO) to VLOG and fix the backward.

* add scale for AF2 flash_attn, much thanks to xreki and shaojie for debug these codes

* decrease the effect of debug print on performance

* Unify the initialize of flashattn arguments.

* Rewirte the reshape of temp_mask and temp_bias.

* API support use_flash_attn.

* Fix compiling error on CI.

* Try to crop the flash-attention lib.

* Correct the condition of whether can use flash-attn.

* Remove the softmax_out argument.

* Remove is_causal.

* Polish codes.

* Fix qkv_transpose_out's shape and scaling of Q * K.

* Update commit of flash-attention.

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Co-authored-by: NLiu Yiqun <liuyiqun01@baidu.com>

* add flash randomness control

* fix VLOG undefied

* Fix flashattn build error on jetson

* Fix nvcc not found on jetson

* flash attn

* seed

* almost

* softmax

* fix workspace

* add unitest; linux only

* fix setup

* fix datatype include

* fix setup typo

* fix def scope

* new error api

* use paddle fork

* fix attr bug; complete ut

* update flash hash

* fix rng reset

* fix offset

* fix comments