CANN: Add the basic supports of Flash Attention kernel (#13627)

* cann: add the basic FA support

* cann: update the readme

* cann: update the FlashAttention with PSEShift

* cann: update the input parameters in FA

* cann: update the alibi with max_bias

* cann: add the constrints of softcap

* cann: update the docs CANN.md

* cann: update the docs CANN.md

* cann: fix typo of CANN.md

* cann: add some comments and update the CANN.md

* cann: update the CANN.md

* cann: update the inner precise for fusedInferAttention

* cann: update the constraints of flash_attn_ext on ggml-cann.cpp

* cann: clean the whitespace

* cann: clean the whitespace

* cann: add a new endline

ggml/src/ggml-cann/acl_tensor.cpp

@@ -31,6 +31,8 @@ aclDataType ggml_cann_type_mapping(ggml_type type) {
             return ACL_FLOAT;
         case GGML_TYPE_F16:
             return ACL_FLOAT16;
+        case GGML_TYPE_BF16:
+            return ACL_BF16;
         case GGML_TYPE_I8:
             return ACL_INT8;
         case GGML_TYPE_I16: