fix(errata): workaround for Cortex-A78C erratum 2395411

Cortex-A78C erratum 2395411 is a Cat B erratum that affects
revisions r0p1 and r0p2, and is currently open. The workaround
is to set CPUACTLR2_EL1[40] to 1, which will disable folding
of demand requests into older prefetches with L2 miss requests
outstanding.

SDEN can be found here:
https://developer.arm.com/documentation/SDEN2004089/latest

Signed-off-by: Akram Ahmad <Akram.Ahmad@arm.com>
Change-Id: I4f0fb278ac20a2eb4dd7e4efd1b1246dd85e48c4
diff --git a/docs/design/cpu-specific-build-macros.rst b/docs/design/cpu-specific-build-macros.rst
index 2ddccac..8e4e240 100644
--- a/docs/design/cpu-specific-build-macros.rst
+++ b/docs/design/cpu-specific-build-macros.rst
@@ -335,6 +335,10 @@
   Cortex-A78C CPU. This needs to be enabled for revisions r0p1, r0p2 and
   it is still open.
 
+- ``ERRATA_A78C_2395411`` : This applies errata 2395411 workaround to
+  Cortex-A78C CPU. This needs to be enabled for revisions r0p1 and r0p2. This
+  erratum is still open.
+
 For Cortex-X1 CPU, the following errata build flags are defined:
 
 - ``ERRATA_X1_1821534`` : This applies errata 1821534 workaround to Cortex-X1