Port the fix to get the PCI_id from asic.conf file from 201911 --> master branch (#7513)

Port the fix to get the pci_device ID from asic.conf file and update the "asic_id" field in DEVICE_METADATA with the pci_device_Id.

Ref: https://github.com/Azure/sonic-buildimage/pull/4705

src/sonic-config-engine/sonic-cfggen

@@ -41,7 +41,7 @@ from functools import partial
 from minigraph import minigraph_encoder, parse_xml, parse_device_desc_xml, parse_asic_sub_role
 from portconfig import get_port_config, get_breakout_mode
 from redis_bcc import RedisBytecodeCache
-from sonic_py_common.multi_asic import get_asic_id_from_name
+from sonic_py_common.multi_asic import get_asic_id_from_name, get_asic_device_id
 from sonic_py_common import device_info
 from swsscommon.swsscommon import SonicV2Connector, ConfigDBConnector, SonicDBConfig, ConfigDBPipeConnector
 
@@ -377,7 +377,12 @@ def main():
             }}}
         # The ID needs to be passed to the SAI to identify the asic.
         if asic_name is not None:
-            hardware_data['DEVICE_METADATA']['localhost'].update(asic_id=asic_id)
+            device_id = get_asic_device_id(asic_id)
+            # if the device_id obtained is None, exit with error
+            if device_id is None:
+                print('Failed to get device ID for', asic_name, file=sys.stderr)
+                sys.exit(1)
+            hardware_data['DEVICE_METADATA']['localhost'].update(asic_id=device_id)
         deep_update(data, hardware_data)
 
     paths = ['/', '/usr/share/sonic/templates']

src/sonic-py-common/sonic_py_common/multi_asic.py

@@ -137,6 +137,29 @@ def get_asic_id_from_name(asic_name):
     else:
         raise ValueError('Unknown asic namespace name {}'.format(asic_name))
 
+def get_asic_device_id(asic_id):
+    # Get asic.conf file
+    asic_conf_file_path = get_asic_conf_file_path()
+
+    if asic_conf_file_path is None:
+        return None
+
+    # In a multi-asic device we need to have the file "asic.conf" updated with the asic instance
+    # and the corresponding device id which could be pci_id. Below is an eg: for a 2 ASIC platform/sku.
+    # DEV_ID_ASIC_0=03:00.0
+    # DEV_ID_ASIC_1=04:00.0
+    device_str = "DEV_ID_ASIC_{}".format(asic_id)
+
+    with open(asic_conf_file_path) as asic_conf_file:
+        for line in asic_conf_file:
+            tokens = line.split('=')
+            if len(tokens) < 2:
+               continue
+            if tokens[0] == device_str:
+                device_id = tokens[1].strip()
+                return device_id
+
+    return None
 
 def get_current_namespace(pid=None):
     """