SPCI is now called PSA FF-A

SPCI is renamed as PSA FF-A which stands for Platform Security
Architecture Firmware Framework for A class processors.
This patch replaces the occurrence of SPCI with PSA FF-A(in documents)
or simply FFA(in code).

Change-Id: I4ab10adb9ffeef1ff784641dfafd99f515133760
Signed-off-by: J-Alves <joao.alves@arm.com>
diff --git a/docs/components/index.rst b/docs/components/index.rst
index e3ce614..c5f6264 100644
--- a/docs/components/index.rst
+++ b/docs/components/index.rst
@@ -17,5 +17,5 @@
    romlib-design
    sdei
    secure-partition-manager-design
-   spci-manifest-binding
+   psa-ffa-manifest-binding
    xlat-tables-lib-v2-design