[TESTS] Enable PL110/PL111 CLCD driver for guest linux

We have PL110/PL111 device available realview-eb-mpcore, realview-pb-a8,
vexpress-a9, and vexpress-a15 guests hence we enable their drivers in
respective guest linux defconfigs.

Signed-off-by: Anup Patel <anup@brainfault.org>