[YANG] Add DPU support in chassis module (#20733)

Why I did it
Add DPU support in CHASSIS_MODULE
Check HLD: https://github.com/sonic-net/SONiC/blob/master/doc/smart-switch/pmon/smartswitch-pmon.md?plain=1#L93-L105

Author: wen587

src/sonic-yang-models/tests/files/sample_config_db.json

@@ -1895,6 +1895,9 @@
             },
             "FABRIC-CARD1": {
                 "admin_status": "down"
+            },
+            "DPU2": {
+                "admin_status": "down"
             }
         },
         "COPP_GROUP": {

src/sonic-yang-models/tests/yang_model_tests/tests_config/chassis_module.json

@@ -18,6 +18,15 @@
                     {
                         "name": "FABRIC-CARD1",
                         "admin_status": "up"
+                    },
+                    {
+                        "name": "DPU0",
+                        "admin_status": "up"
+                    },
+                    {
+                        "name": "DPU1",
+                        "admin_status": "up"
+                     
                     }
                 ]
             }
@@ -34,6 +43,10 @@
                     {
                         "name": "FABRIC-CARD1",
                         "admin_status": "down"
+                    },
+                    {
+                        "name": "DPU2",
+                        "admin_status": "down"
                     }
                 ]
             }

src/sonic-yang-models/yang-models/sonic-chassis-module.yang

@@ -20,9 +20,9 @@ module sonic-chassis-module {
                 key "name";
                 leaf name {
                     type string {
-                        pattern "LINE-CARD[0-9]+|FABRIC-CARD[0-9]+";
+                        pattern "LINE-CARD[0-9]+|FABRIC-CARD[0-9]+|DPU[0-9]+";
                     }
-                    description "Line-card or fabric-card module name";
+                    description "Line-card or fabric-card or dpu module name";
                 }
 
                 leaf admin_status {