revert(cpus): "Revert workaround for A77 erratum 1800714"

Reinstate the workaround introduced in commit
9bbc03a6e0608a949d66d9da6db12a455b452bfb. The cited change to the SDEN
could not be found and there are no known problems with the workaround.

Signed-off-by: Boyan Karatotev <boyan.karatotev@arm.com>
Change-Id: Iec9938f173e7565024aca798f224df339de90806
diff --git a/lib/cpus/cpu-ops.mk b/lib/cpus/cpu-ops.mk
index 08871f8..8b790bc 100644
--- a/lib/cpus/cpu-ops.mk
+++ b/lib/cpus/cpu-ops.mk
@@ -307,6 +307,10 @@
 # to revisions r0p0, r1p0, and r1p1, it is still open.
 ERRATA_A77_2356587	?=0
 
+# Flag to apply erratum 1800714 workaround during reset. This erratum applies
+# to revisions <= r1p1 of the Cortex A77 cpu.
+ERRATA_A77_1800714	?=0
+
 # Flag to apply erratum 1688305 workaround during reset. This erratum applies
 # to revisions r0p0 - r1p0 of the A78 cpu.
 ERRATA_A78_1688305	?=0
@@ -912,6 +916,10 @@
 $(eval $(call assert_boolean,ERRATA_A77_2356587))
 $(eval $(call add_define,ERRATA_A77_2356587))
 
+# Process ERRATA_A77_1800714 flag
+$(eval $(call assert_boolean,ERRATA_A77_1800714))
+$(eval $(call add_define,ERRATA_A77_1800714))
+
 # Process ERRATA_A78_1688305 flag
 $(eval $(call assert_boolean,ERRATA_A78_1688305))
 $(eval $(call add_define,ERRATA_A78_1688305))