meta-facebook: harma: add getty in ttyS3

This function allows CMM to log in to the host BMC for debugging.

Path:
CMM UART6 Host -> Harma Uart6 getty -> SITV Uart2 getty

Change-Id: I2137b2fd3d7dd18b500effc7c1f5e765498fadb0
Signed-off-by: Peter Yin <peter.yin@quantatw.com>
diff --git a/meta-facebook/meta-harma/conf/machine/harma.conf b/meta-facebook/meta-harma/conf/machine/harma.conf
index 83f22a1..ea918b9 100644
--- a/meta-facebook/meta-harma/conf/machine/harma.conf
+++ b/meta-facebook/meta-harma/conf/machine/harma.conf
@@ -23,3 +23,5 @@
 
 VIRTUAL-RUNTIME_obmc-host-state-manager = "phosphor-state-manager-host"
 VIRTUAL-RUNTIME_obmc-chassis-state-manager = "phosphor-state-manager-chassis"
+
+SERIAL_CONSOLES += " 57600;ttyS3"