purin: add ns16550 driver

BUG=chrome-os-partner:35807
BRANCH=broadcom-firmware
TEST=booted b0 board. messages printed on console:

coreboot-bcf5dc0-dirty bootblock Mon Feb  9 13:33:55 PST 2015 starting...
Exception handlers installed.

Change-Id: I271ead2f4fe48b809fd311acd5a27a675dce549e
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: ddff8fb170e775a121150fce065410d2925ad18c
Original-Signed-off-by: Daisuke Nojiri <dnojiri@chromium.org>
Original-Change-Id: Ia6e82fa89547d61745c1473f723897dc3c1296ef
Original-Reviewed-on: https://chromium-review.googlesource.com/251301
Original-Reviewed-by: Julius Werner <jwerner@chromium.org>
Reviewed-on: http://review.coreboot.org/9765
Tested-by: build bot (Jenkins)
Reviewed-by: Edward O'Callaghan <edward.ocallaghan@koparo.com>
diff --git a/src/soc/broadcom/cygnus/Kconfig b/src/soc/broadcom/cygnus/Kconfig
index 158f61c..2ccc306 100644
--- a/src/soc/broadcom/cygnus/Kconfig
+++ b/src/soc/broadcom/cygnus/Kconfig
@@ -39,4 +39,9 @@
 	string
 	default "soc/broadcom/cygnus/bootblock.c"
 
+config CONSOLE_SERIAL_UART_ADDRESS
+	hex
+	depends on CONSOLE_SERIAL_UART
+	default 0x18023000
+
 endif