OvmfPkg/PlatformDxe: Check RouteConfig arguments for spec compliance

Per UEFI Spec 2.9, EFI_HII_CONFIG_ROUTING_PROTOCOL.RouteConfig()
should return EFI_INVALID_PARAMETER if caller passes in a NULL for
the Configuration parameter (see 35.4 EFI HII Configuration Routing
Protocol).

Add a check to return EFI_INVALID_PARAMETER when Configuration is NULL.

Signed-off-by: Yuan Yu <yuanyu@google.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>

OvmfPkg/PlatformDxe/Platform.c

@@ -344,7 +344,7 @@ RouteConfig (
     Configuration
     ));
 
-  if (Progress == NULL) {
+  if ((Progress == NULL) || (Configuration == NULL)) {
     return EFI_INVALID_PARAMETER;
   }