[msft-202405][yang-model] support reserving mem in high region for crashkernel (#1851)

Why I did it
Cherry-pick sonic-net/sonic-buildimage#24441 in msft-202405.

Work item tracking
Microsoft ADO (number only):

Author: ysmanman

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

@@ -11,12 +11,26 @@
     "KDUMP_WITH_VALID_VALUES_4": {
         "desc": "Configuring the kdump with valid values."
     },
+    "KDUMP_WITH_VALID_MEM_HIGH": {
+        "desc": "Configuring the kdump with valid values and high suffix."
+    },
+    "KDUMP_WITH_VALID_MEM_HIGH_2": {
+        "desc": "Configuring the kdump with valid values and high suffix."
+    },
     "KDUMP_WITH_INVALID_NUM_DUMPS": {
         "desc": "Configuring kdump config with a invalid number of allowed kdumps.",
         "eStr": ["pattern", "does not satisfy"]
     },
     "KDUMP_WITH_INVALID_MEMORY": {
         "desc": "Configuring kdump config with invalid memory config.",
         "eStr": ["pattern", "does not satisfy"]
+    },
+    "KDUMP_WITH_INVALID_MEM_HIGH": {
+        "desc": "Configuring kdump config with invalid value.",
+        "eStr": ["Pattern", "does not satisfy"]
+    },
+    "KDUMP_WITH_INVALID_MEM_HIGH_2": {
+        "desc": "Configuring kdump config with invalid suffix.",
+        "eStr": ["Pattern", "does not satisfy"]
     }
 }

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

@@ -43,7 +43,28 @@
             }
         }
     },
-
+    "KDUMP_WITH_VALID_MEM_HIGH": {
+        "sonic-kdump:sonic-kdump": {
+            "sonic-kdump:KDUMP": {
+                "config": {
+                    "enabled": "true",
+                    "num_dumps": "3",
+                    "memory": "1G,high",
+                }
+            }
+        }
+    },
+    "KDUMP_WITH_VALID_MEM_HIGH_2": {
+        "sonic-kdump:sonic-kdump": {
+            "sonic-kdump:KDUMP": {
+                "config": {
+                    "enabled": "true",
+                    "num_dumps": "3",
+                    "memory": "512M,high",
+                }
+            }
+        }
+    },
     "KDUMP_WITH_INVALID_NUM_DUMPS": {
         "sonic-kdump:sonic-kdump": {
             "sonic-kdump:KDUMP": {
@@ -65,5 +86,27 @@
                 }
             }
         }
+    },
+    "KDUMP_WITH_INVALID_MEM_HIGH": {
+        "sonic-kdump:sonic-kdump": {
+            "sonic-kdump:KDUMP": {
+                "config": {
+                    "enabled": "true",
+                    "num_dumps": "3",
+                    "memory": "100,high",
+                }
+            }
+        }
+    },
+    "KDUMP_WITH_INVALID_MEM_HIGH_2": {
+        "sonic-kdump:sonic-kdump": {
+            "sonic-kdump:KDUMP": {
+                "config": {
+                    "enabled": "true",
+                    "num_dumps": "3",
+                    "memory": "1G,highx",
+                }
+            }
+        }
     }
 }

src/sonic-yang-models/yang-models/sonic-kdump.yang

@@ -33,7 +33,7 @@ module sonic-kdump {
 
                 leaf memory {
                     type string {
-                        pattern "(((([0-9]+[MG]?)?(-([0-9]+[MG])?):)?[0-9]+[MG],?)+)";
+                        pattern "((((([0-9]+[MG]?)?(-([0-9]+[MG])?):)?[0-9]+[MG],?)+)|([0-9]+[MG],high))";
                     }
                     description
                         "Memory reserved for loading the crash handler kernel. The amount