Platform: Add FVP_SSE300_MPS2 target

Add support for FVP_SSE300_MPS2 platform

Change-Id: Ieddb5adbdc0cc47690bbe0b3dfbaf39d005d03ea
Signed-off-by: Mark Horvath <mark.horvath@arm.com>
Signed-off-by: Marton Berke <marton.berke@arm.com>
diff --git a/docs/readme.rst b/docs/readme.rst
index 51657c5..c0d6d0a 100644
--- a/docs/readme.rst
+++ b/docs/readme.rst
@@ -88,6 +88,11 @@
 ###################
 Platforms supported
 ###################
+    - Cortex-M55 system:
+
+        - `Fast model FVP_SSE300_MPS2.
+          <https://developer.arm.com/tools-and-software/open-source-software/arm-platforms-software/arm-ecosystem-fvps>`_
+
     - Cortex-M33 system:
 
         - `FPGA image loaded on MPS2 board.