feat(tcr2): support FEAT_TCR2

Arm v8.9 introduces FEAT_TCR2, adding extended translation control
registers. Support this, context switching TCR2_EL2 and disabling
traps so lower ELs can access the new registers.

Change the FVP platform to default to handling this as a dynamic option so
the right decision can be made by the code at runtime.

Signed-off-by: Mark Brown <broonie@kernel.org>
Change-Id: I297452acd8646d58bac64fc15e05b06a543e5148
diff --git a/common/feat_detect.c b/common/feat_detect.c
index 5fb56b9..4099732 100644
--- a/common/feat_detect.c
+++ b/common/feat_detect.c
@@ -314,6 +314,10 @@
 	/* v8.7 features */
 	check_feature(ENABLE_FEAT_HCX, read_feat_hcx_id_field(), "HCX", 1, 1);
 
+	/* v8.9 features */
+	check_feature(ENABLE_FEAT_TCR2, read_feat_tcrx_id_field(),
+		      "TCR2", 1, 1);
+
 	/* v9.0 features */
 	check_feature(ENABLE_BRBE_FOR_NS, read_feat_brbe_id_field(),
 		      "BRBE", 1, 2);