Enable serial from morph too

Signed-off-by: Benoit Donneaux <benoit@leastauthority.com>

morph/lib/hardware-vagrant.nix

@@ -21,6 +21,7 @@
 
     boot.initrd.availableKernelModules = [ "ata_piix" "sd_mod" "sr_mod" ];
     boot.kernel.sysctl = { "vm.swappiness" = 0; };
+    boot.kernelParams = [ "console=tty0" "console=ttyS0,115200" ];
 
     # remove the fsck that runs at startup. It will always fail to run, stopping
     # your boot until you press *.