[YANG] Update range of supported port speeds to support 800G ports (#10687)

- Why I did it
To add support for 800G speed for port in the yang.

- How I did it
Change limitation from 400G to 800G.

- How to verify it
Set a port speed to 800G and run the yang DB validation. e.g. by using dynamic port breakout.

src/sonic-yang-models/tests/yang_model_tests/tests/port.json

@@ -24,6 +24,13 @@
         "eStrKey" : "Pattern",
         "eStr": ["on|off"]
     },
+    "PORT_VALID_SPEEDS_TEST_1": {
+        "desc": "PORT_VALID_SPEEDS_TEST_1 no failure."
+    },
+    "PORT_INVALID_SPEEDS_TEST_1": {
+        "desc": "PORT_INVALID_SPEEDS_TEST_1 InvalidValue condition failure.",
+        "eStr": ["pattern", "does not satisfy"]
+    },
     "PORT_VALID_ADVSPEEDS_TEST_1": {
         "desc": "PORT_VALID_ADVSPEEDS_TEST_1 no failure."
     },

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

@@ -90,6 +90,40 @@
         }
     },
 
+    "PORT_VALID_SPEEDS_TEST_1": {
+        "sonic-port:sonic-port": {
+            "sonic-port:PORT": {
+                "PORT_LIST": [
+                    {
+                        "name": "Ethernet8",
+                        "alias": "eth8",
+                        "lanes": "65",
+                        "speed": 800000,
+                        "autoneg": "on",
+                        "adv_speeds": [400000, 800000]
+                    }
+                ]
+            }
+        }
+    },
+
+    "PORT_INVALID_SPEEDS_TEST_1": {
+        "sonic-port:sonic-port": {
+            "sonic-port:PORT": {
+                "PORT_LIST": [
+                    {
+                        "name": "Ethernet8",
+                        "alias": "eth8",
+                        "lanes": "65",
+                        "speed": 900000,
+                        "autoneg": "on",
+                        "adv_speeds": [25000,40000]
+                    }
+                ]
+            }
+        }
+    },
+
     "PORT_VALID_ADVSPEEDS_TEST_1": {
         "sonic-port:sonic-port": {
             "sonic-port:PORT": {
@@ -124,6 +158,23 @@
         }
     },
 
+    "PORT_VALID_ADVSPEEDS_TEST_3": {
+        "sonic-port:sonic-port": {
+            "sonic-port:PORT": {
+                "PORT_LIST": [
+                    {
+                        "name": "Ethernet8",
+                        "alias": "eth8",
+                        "lanes": "65",
+                        "speed": 25000,
+                        "autoneg": "on",
+                        "adv_speeds": [25000,800000]
+                    }
+                ]
+            }
+        }
+    },
+
     "PORT_INVALID_ADVSPEEDS_TEST_1": {
         "sonic-port:sonic-port": {
             "sonic-port:PORT": {

src/sonic-yang-models/yang-models/sonic-port.yang

@@ -61,7 +61,7 @@ module sonic-port{
 				leaf speed {
 					mandatory true;
 					type uint32 {
-						range 1..400000;
+						range 1..800000;
 					}
 				}
 
@@ -78,7 +78,7 @@ module sonic-port{
 					
 					type union {
 						type uint32 {
-							range 1..400000;
+							range 1..800000;
 						}
 						type string {
 							pattern "all";