[EMULATORS] Introduce PL110 AMBA CLCD emulator

This patch adds PL110/PL111 AMBA CLCD emulator adapted from QEMU
sources. This will be a virtual AMBA CLCD that will be available
to most of the ARM guest as framebuffer/video device.

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