[Mellanox] enable 'create_only_config_db_buffers' to optimize counters polling for Mellanox-SN4700-V64 (sonic-net#22225)

- Why I did it
Need to optimize counters polling for Mellanox-SN4700-V64

- How I did it
Set "create_only_config_db_buffers" in config_db to "true"

- How to verify it
run config reload and check initialization sequence

Signed-off-by: Andriy Yurkiv <[email protected]>

Author: ayurkiv-nvda

device/mellanox/x86_64-mlnx_msn4700-r0/Mellanox-SN4700-V64/create_only_config_db_buffers.json

@@ -0,0 +1,7 @@
+{
+    "DEVICE_METADATA": {
+        "localhost": {
+            "create_only_config_db_buffers": "true"
+        }
+    }
+}