add wasm cpu

Signed-off-by: Lizan Zhou <lizan@tetrate.io>
diff --git a/cpu/BUILD b/cpu/BUILD
index 80c9c38..e06de69 100644
--- a/cpu/BUILD
+++ b/cpu/BUILD
@@ -74,3 +74,13 @@
     name = "x86_64",
     constraint_setting = ":cpu",
 )
+
+constraint_value(
+    name = "wasm32",
+    constraint_setting = ":cpu",
+)
+
+constraint_value(
+    name = "wasm64",
+    constraint_setting = ":cpu",
+)