docs: remove deprecated tc0 from list of supported FVPs

TC0 is now a deprecated platform so remove it from the list
of supported FVPs as well as throwing an error if it is attempted
to be built.

Signed-off-by: Daniel Boulby <daniel.boulby@arm.com>
Change-Id: Id013fcecbe20700611463ef9eab8cb3ae09071cc
diff --git a/docs/plat/arm/tc/index.rst b/docs/plat/arm/tc/index.rst
index df1847d..925befc 100644
--- a/docs/plat/arm/tc/index.rst
+++ b/docs/plat/arm/tc/index.rst
@@ -17,7 +17,7 @@
 (TARGET_PLATFORM=1), TC2 (TARGET_PLATFORM=2) platforms w.r.t to TF-A
 is the CPUs supported as below:
 
--  TC0 has support for Cortex A510, Cortex A710 and Cortex X2.
+-  TC0 has support for Cortex A510, Cortex A710 and Cortex X2. (Note TC0 is now deprecated)
 -  TC1 has support for Cortex A510, Cortex Makalu and Cortex X3.
 -  TC2 has support for Hayes and Hunter Arm CPUs.