New-AzVm and New-AzVmConfig licenseType description edits (#13407)

* licensetype description edits for New-AzVm and New-AzVmConfig

* updated descriptions based on feedback

Author: Sandido

src/Compute/Compute/help/New-AzVM.md

@@ -396,12 +396,12 @@ Accept wildcard characters: False
 
 ### -LicenseType
 Specifies a license type, which indicates that the image or disk for the virtual machine was licensed on-premises.
-This value is used only for images that contain the Windows Server operating system.
-The acceptable values for this parameter are:
+Possible values for Windows Server are:
 - Windows_Client
 - Windows_Server
-This value cannot be updated.
-If you specify this parameter for an update, the value must match the initial value for the virtual machine.
+Possible values for Linux Server operating system are: 
+- RHEL_BYOS (for RHEL) 
+- SLES_BYOS (for SUSE) 
 
 ```yaml
 Type: System.String

src/Compute/Compute/help/New-AzVMConfig.md

@@ -166,7 +166,13 @@ Accept wildcard characters: False
 ```
 
 ### -LicenseType
-The license type, which is for bringing your own license scenario.
+Specifies a license type, which indicates that the image or disk for the virtual machine was licensed on-premises.
+Possible values for Windows Server are:
+- Windows_Client
+- Windows_Server
+Possible values for Linux Server operating system are: 
+- RHEL_BYOS (for RHEL) 
+- SLES_BYOS (for SUSE) 
 
 ```yaml
 Type: System.String