model: enable secure uart for sgi575 platform

Add new model parameter to enable secure uart for sgi575 platform.

Signed-off-by: Rohit Mathew <rohit.mathew@arm.com>
Change-Id: I5ed85d6a11d74648a439d48b1bca6704039913c2
diff --git a/model/css-sgi575.sh b/model/css-sgi575.sh
index 873baba..06561ad 100644
--- a/model/css-sgi575.sh
+++ b/model/css-sgi575.sh
@@ -15,6 +15,7 @@
 -C css.gic_distributor.ITS-device-bits=20
 -C css.mcp.ROMloader.fname=$mcp_rom_bin
 -C css.pl011_uart_ap.unbuffered_output=1
+-C css.pl011_uart1_ap.unbuffered_output=1
 -C css.scp.ROMloader.fname=$scp_rom_bin
 -C css.trustedBootROMloader.fname=$bl1_bin
 -C soc.pl011_uart_mcp.unbuffered_output=1