Cortex-A55: Implement workaround for erratum 903758

Change-Id: I07e69061ba7a918cdfaaa83fa3a42dee910887d7
Signed-off-by: Ambroise Vincent <ambroise.vincent@arm.com>
diff --git a/docs/cpu-specific-build-macros.rst b/docs/cpu-specific-build-macros.rst
index 85e5642..ea831b7 100644
--- a/docs/cpu-specific-build-macros.rst
+++ b/docs/cpu-specific-build-macros.rst
@@ -111,6 +111,9 @@
 -  ``ERRATA_A55_846532``: This applies errata 846532 workaround to Cortex-A55
    CPU. This needs to be enabled only for revision <= r0p1 of the CPU.
 
+-  ``ERRATA_A55_903758``: This applies errata 903758 workaround to Cortex-A55
+   CPU. This needs to be enabled only for revision <= r0p1 of the CPU.
+
 For Cortex-A57, the following errata build flags are defined :
 
 -  ``ERRATA_A57_806969``: This applies errata 806969 workaround to Cortex-A57