ARM: vexpress/mps2: introduce MPS2 platform

The Cortex-M Prototyping System (or V2M-MPS2) is designed for
prototyping and evaluation Cortex-M family of processors including the
latest Cortex-M7

It comes with a range of useful peripherals including 8MB single cycle
SRAM, 16MB PSRAM, Ethernet, QSVGA touch screen panel, 4bit RGB VGA
connector, Audio, SPI and GPIO.

Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
diff --git a/arch/arm/Makefile b/arch/arm/Makefile
index 8c3ce2a..274e8a6 100644
--- a/arch/arm/Makefile
+++ b/arch/arm/Makefile
@@ -183,6 +183,7 @@
 machine-$(CONFIG_ARCH_LPC32XX)		+= lpc32xx
 machine-$(CONFIG_ARCH_MESON)		+= meson
 machine-$(CONFIG_ARCH_MMP)		+= mmp
+machine-$(CONFIG_ARCH_MPS2)		+= vexpress
 machine-$(CONFIG_ARCH_MOXART)		+= moxart
 machine-$(CONFIG_ARCH_MV78XX0)		+= mv78xx0
 machine-$(CONFIG_ARCH_MVEBU)		+= mvebu