* fix for matmul_grad

* another fix for matmul_grad

* fix

* remove layers.matmul in nets.py

* remove layers.matmul in rnn_impl/test_quantization_pass/auto_parallel_gpt_model/test_auto_parallel_completion_gpt

* remove layers.matmul in other files

* fix

* fix

* remove layers.matmul itself

* remove ref in CMakeLists.txt and tools directory

* remove matmul in fluid.layers.nn.py

* remove matmul in fluid.dygraph.rnn.py && resotre test_matmul_op.py

* replace matmul in fluid.dygraph.rnn.py && clean api_test in test_matmul_op.py

* fix error && restore empty test_auto_search_dist_matmul_op.py

* fix check in test_auto_parallel_partitioner.py

* fix test_dist_matmul && test_flags_mkldnn_ops_on_off

* fix test_fused_attention_op_xpu.py && test_matmul_op_xpu.py

* remove test_auto_search_dist_matmul_op.py

* remove layers.matmul in auto_parallel_gpt_model.py && fix doc in fluid/io.py

* fix for matmul_grad

* fix codestyle

* fix codestyle

* resolve conflicts error

* restore unit test file but not compiled it for later remove

* fix codestyle

* fix wrong unittest skip

* fix unittest delete

* fix scale cost

* fix scale cost

* resolve conflicts error

* resolve conflicts error
Co-authored-by: Njakpiase <jakpia21@gmail.com>

* cleanup unused code

* unify is_int8 is_bfloat16

* Simplify matmul_v2 FWD kernel

* remove RunKernel methods

* remove import namespace

* remove headers

* clean fluid/phi cross imports

* remove fluid axpy_handler

* delete fluid methods

* activations

* OneDNNMemDesc

* MKLDNNFormatForSize

* MatchShapeToLayout

* MKLDNNMemoryFormat

* MKLDNNFormat

* ReorderMKLDNNHandler

* to_void_cast

* review suggestions

* interpolate

* remove fluid depedency

* init

* ExecuteMatMulV2

* rm fluid kernel

* matmul_grad

* remove mutable_data

* mul_grad

* cleanup unused code

* unify is_int8 is_bfloat16

* Simplify matmul_v2 FWD kernel

* remove RunKernel methods

* remove import namespace

* remove headers

* clean fluid/phi cross imports

* remove fluid axpy_handler

* delete fluid methods

* activations

* OneDNNMemDesc

* MKLDNNFormatForSize

* MatchShapeToLayout

* MKLDNNMemoryFormat

* MKLDNNFormat

* ReorderMKLDNNHandler

* to_void_cast

* review suggestions

* interpolate

* remove fluid depedency

* init

* ExecuteMatMulV2

* rm fluid kernel

* matmul_grad

* remove mutable_data