sh: Add additional ttySCs

There are a couple of Renesas SH devices with 8 serial ports used.

Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

fs/skeleton/etc/securetty

@@ -46,4 +46,6 @@ ttySC2
 ttySC3
 ttySC4
 ttySC5
+ttySC6
+ttySC7
 ttyGS0

target/generic/device_table_dev.txt

@@ -32,7 +32,7 @@
 /dev/ttyCPM	c	666	0	0	204	46	0	1	4
 /dev/ttyAMA	c	666	0	0	204	64	0	1	4
 /dev/ttySAC	c	666	0	0	204	64	0	1	4
-/dev/ttySC	c	666	0	0	204	8	0	1	6
+/dev/ttySC	c	666	0	0	204	8	0	1	8
 /dev/ttyPSC	c	666	0	0	204	148	0	1	4
 /dev/ttyUL	c	666	0	0	204	187	0	1	4
 /dev/ttymxc	c	666	0	0	207	16	0	1	3