arch: acpi: Only add ACPI COM1 device if serial is turned on

Only add the ACPI PNP device for the COM1 serial port if it is not
turned off with "--serial off"

Signed-off-by: Rob Bradford <robert.bradford@intel.com>

arch/src/aarch64/mod.rs

@@ -16,6 +16,7 @@ pub fn configure_system(
     _cmdline_addr: GuestAddress,
     _cmdline_size: usize,
     _num_cpus: u8,
+    _serial_enabled: bool,
 ) -> super::Result<()> {
     Ok(())
 }