### What this PR does / why we need it?
The recommended configuration in the document kv_pool.md is ascend.
Modify the default value of the protocol to ascend，Improve usability
#### 1.Configure mooncake.json
The environment variable **MOONCAKE_CONFIG_PATH** is configured to the
full path where mooncake.json is located.
```
{
"local_hostname": "xx.xx.xx.xx",
"metadata_server": "P2PHANDSHAKE",
"protocol": "ascend",
"device_name": "",
"alloc_in_same_node": true,
"master_server_address": "xx.xx.xx.xx:50088",
"global_segment_size": "1GB" (1024MB/1048576KB/1073741824B/1073741824)
}
```
**local_hostname**: Configured as the IP address of the current master
node.
**metadata_server**: Configured as **P2PHANDSHAKE**.
**protocol:** Configured for Ascend to use Mooncake's HCCL
communication.
**device_name**: ""
**alloc_in_same_node**: Indicator for preferring local buffer allocation
strategy.
**master_server_address**: Configured with the IP and port of the master
service.
**global_segment_size**: Expands the kvcache size registered by the PD
node to the master.
### Does this PR introduce _any_ user-facing change?
No
### How was this patch tested?
Mooncake does not set up a protocol to launch the pooled VLLM service;
test whether the pooling function is working.
Signed-off-by: lty <linhebiwen@gmail.com>
0cdf98ac48