target/s390x: Implement CSST

Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
diff --git a/target/s390x/cpu_models.c b/target/s390x/cpu_models.c
index c654279..8433010 100644
--- a/target/s390x/cpu_models.c
+++ b/target/s390x/cpu_models.c
@@ -787,6 +787,8 @@
         S390_FEAT_ETF2_ENH,
         S390_FEAT_STORE_CLOCK_FAST,
         S390_FEAT_MOVE_WITH_OPTIONAL_SPEC,
+        S390_FEAT_COMPARE_AND_SWAP_AND_STORE,
+        S390_FEAT_COMPARE_AND_SWAP_AND_STORE_2,
         S390_FEAT_GENERAL_INSTRUCTIONS_EXT,
         S390_FEAT_EXECUTE_EXT,
         S390_FEAT_FLOATING_POINT_SUPPPORT_ENH,