Remove Platform.SupportsRemoveDrive query

src/System.Management.Automation/CoreCLR/CorePsPlatform.cs

@@ -217,12 +217,6 @@ namespace System.Management.Automation
 
         }
 
-        // non-windows does not support removing drives
-        internal static bool SupportsRemoveDrive()
-        {
-            return IsWindows;
-        }
-
         // Platform methods prefixed NonWindows are:
         // - non-windows by the definition of the IsWindows method above
         // - here, because porting to Linux and other operating systems

src/System.Management.Automation/namespaces/FileSystemProvider.cs

@@ -607,15 +607,11 @@ namespace Microsoft.PowerShell.Commands
         /// </returns>
         protected override PSDriveInfo RemoveDrive(PSDriveInfo drive)
         {
-            // if removing the drive is not supported, just return the drive
-            if (Platform.SupportsRemoveDrive())
-            {
-                return WinRemoveDrive(drive);
-            }
-            else
-            {
-                return drive;
-            }
+#if LINUX
+            return drive;
+#else
+            return WinRemoveDrive(drive);
+#endif
         }
 
         private PSDriveInfo WinRemoveDrive(PSDriveInfo drive)