Add one more virtio-console device

To be in sync with Cuttlefish, have three virtio-console devices
(previously two) in Microdroid.

/dev/hvc0 is used as the kernel console where kmsg is redirected to
/dev/hvc1 is a new one and is used as the userspace console (set via
androidboot.console). This currently is not used; the backend is a sink.
/dev/hvc2 is used for logcat output

Bug: 200914564
Test: run MicrodroidDemoApp
Change-Id: Ib51be683cc2f8e19e09ae7a6b5707a196eb93ac5
diff --git a/microdroid/init.rc b/microdroid/init.rc
index ad551cc..664402f 100644
--- a/microdroid/init.rc
+++ b/microdroid/init.rc
@@ -195,7 +195,7 @@
     seclabel u:r:shell:s0
     setenv HOSTNAME console
 
-service seriallogging /system/bin/logcat -b all -v threadtime -f /dev/hvc1 *:V
+service seriallogging /system/bin/logcat -b all -v threadtime -f /dev/hvc2 *:V
     disabled
     user logd
     group root logd