fix(errata): workaround for Cortex X2 erratum 2083908

Cortex X2 erratum 2083908 is a Cat B erratum present in the Cortex
X2 core. It applies to revision r2p0 and is still open.

SDEN can be found here:
https://developer.arm.com/documentation/SDEN1775100

Signed-off-by: John Powell <john.powell@arm.com>
Change-Id: Id9dca2b042bf48e75fb3013ab37d1c5925824728
diff --git a/lib/cpus/cpu-ops.mk b/lib/cpus/cpu-ops.mk
index a5b8aae..c3d2a4a 100644
--- a/lib/cpus/cpu-ops.mk
+++ b/lib/cpus/cpu-ops.mk
@@ -495,6 +495,10 @@
 # to revision r0p0, r1p0 and r2p0 of the Cortex-A710 cpu and is still open.
 ERRATA_A710_2017096	?=0
 
+# Flag to apply erratum 2083908 workaround during reset. This erratum applies
+# to revision r2p0 of the Cortex-X2 cpu and is still open.
+ERRATA_X2_2083908   ?=0
+
 # Flag to apply DSU erratum 798953. This erratum applies to DSUs revision r0p0.
 # Applying the workaround results in higher DSU power consumption on idle.
 ERRATA_DSU_798953	?=0
@@ -920,6 +924,10 @@
 $(eval $(call assert_boolean,ERRATA_A710_2017096))
 $(eval $(call add_define,ERRATA_A710_2017096))
 
+# Process ERRATA_X2_2083908 flag
+$(eval $(call assert_boolean,ERRATA_X2_2083908))
+$(eval $(call add_define,ERRATA_X2_2083908))
+
 # Process ERRATA_DSU_798953 flag
 $(eval $(call assert_boolean,ERRATA_DSU_798953))
 $(eval $(call add_define,ERRATA_DSU_798953))