Cortex-A73: Implement workaround for errata 852427

In AArch32, execution of 2 instructions with opposite condition code
might lead to either a data corruption or a CPU deadlock. Set the bit
12 of the Diagnostic Register to prevent this.

Change-Id: I22b4f25fe933e2942fd785e411e7c0aa39d5c1f4
Signed-off-by: Louis Mayencourt <louis.mayencourt@arm.com>
diff --git a/docs/cpu-specific-build-macros.rst b/docs/cpu-specific-build-macros.rst
index 1f23b5b..116b4ba 100644
--- a/docs/cpu-specific-build-macros.rst
+++ b/docs/cpu-specific-build-macros.rst
@@ -134,6 +134,9 @@
 
 For Cortex-A73, the following errata build flags are defined :
 
+-  ``ERRATA_A73_852427``: This applies errata 852427 workaround to Cortex-A73
+   CPU. This needs to be enabled only for revision r0p0 of the CPU.
+
 -  ``ERRATA_A73_855423``: This applies errata 855423 workaround to Cortex-A73
    CPU. This needs to be enabled only for revision <= r0p1 of the CPU.