feat: add v1.1 platform

Add a copy of the `aem_v8a_fvp_vhe` platform with FF-A version v1.1

Change-Id: I6e1ec6a0db6d74952d7440811f8b5107a7669a27
Signed-off-by: Karl Meakin <karl.meakin@arm.com>
diff --git a/docs/getting_started/building.rst b/docs/getting_started/building.rst
index 500e5b8..8b7c704 100644
--- a/docs/getting_started/building.rst
+++ b/docs/getting_started/building.rst
@@ -45,7 +45,7 @@
 
 .. code:: shell
 
-    Supported platforms:  ['secure_rd_fremont', 'secure_rd_fremont_cfg1', 'secure_aem_v8a_fvp_vhe', 'aem_v8a_fvp_vhe', 'qemu_aarch64_vhe', 'secure_qemu_aarch64', 'rpi4', 'secure_tc']
+    Supported platforms:  ['secure_rd_fremont', 'secure_rd_fremont_cfg1', 'secure_aem_v8a_fvp_vhe', 'aem_v8a_fvp_vhe', 'aem_v8a_fvp_vhe_ffa_v1_1', 'qemu_aarch64_vhe', 'secure_qemu_aarch64', 'rpi4', 'secure_tc']
 
 Additional options
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