chore: rename Makalu ELP to Cortex-X3

The Cortex-X3 cpu port was developed before its public release when it
was known as Makalu ELP. Now that it's released we can use the official
product name.

Signed-off-by: Boyan Karatotev <boyan.karatotev@arm.com>
Change-Id: Iebb90cf2f77330ed848a3d61c5f6928942189c5a
diff --git a/docs/security_advisories/security-advisory-tfv-9.rst b/docs/security_advisories/security-advisory-tfv-9.rst
index a4db17d..08bfdc4 100644
--- a/docs/security_advisories/security-advisory-tfv-9.rst
+++ b/docs/security_advisories/security-advisory-tfv-9.rst
@@ -71,12 +71,12 @@
 +----------------------+
 | Cortex-X2            |
 +----------------------+
+| Cortex-X3            |
++----------------------+
 | Cortex-A710          |
 +----------------------+
 | Cortex-Makalu        |
 +----------------------+
-| Cortex-Makalu-ELP    |
-+----------------------+
 | Cortex-Hunter        |
 +----------------------+
 | Neoverse-N1          |