ARM: shmobile: lager: Rename SCIFA[01] serial ports to ttySC[01]

There's no reason to name the only two available serial ports on the
board ttySC6 and ttySC7 (apart from confusing userspace, which we should
try to avoid).

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

arch/arm/boot/dts/r8a7790-lager.dts

@@ -47,12 +47,12 @@
 	compatible = "renesas,lager", "renesas,r8a7790";
 
 	aliases {
-		serial6 = &scifa0;
-		serial7 = &scifa1;
+		serial0 = &scifa0;
+		serial1 = &scifa1;
 	};
 
 	chosen {
-		bootargs = "console=ttySC6,115200 ignore_loglevel rw root=/dev/nfs ip=dhcp";
+		bootargs = "console=ttySC0,115200 ignore_loglevel rw root=/dev/nfs ip=dhcp";
 		stdout-path = &scifa0;
 	};