docs: list removal of fvp_r

Commit 2cadf21bc removed fvp_r but did not list it as such. Do that.

Change-Id: I84e83196add3d0f912fd503cd253bc5496647dd6
Signed-off-by: Boyan Karatotev <boyan.karatotev@arm.com>
diff --git a/docs/plat/index.rst b/docs/plat/index.rst
index 0b53d1d..15b1d91 100644
--- a/docs/plat/index.rst
+++ b/docs/plat/index.rst
@@ -76,7 +76,10 @@
 |      TC2       |      Arm       |        2.12        |         TBD        |
 |                |                |                    |                    |
 +----------------+----------------+--------------------+--------------------+
+|     fvp_r      |      Arm       |        2.13        |         2.13       |
+|                |                |                    |                    |
++----------------+----------------+--------------------+--------------------+
 
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+*Copyright (c) 2019-2025, Arm Limited. All rights reserved.*