py: Use mp_raise_TypeError/mp_raise_ValueError helpers where possible.

Saves 168 bytes on bare-arm.
diff --git a/py/builtinevex.c b/py/builtinevex.c
index b0514ee..89fcc2f 100644
--- a/py/builtinevex.c
+++ b/py/builtinevex.c
@@ -95,7 +95,7 @@
         case MP_QSTR_exec: parse_input_kind = MP_PARSE_FILE_INPUT; break;
         case MP_QSTR_eval: parse_input_kind = MP_PARSE_EVAL_INPUT; break;
         default:
-            mp_raise_msg(&mp_type_ValueError, "bad compile mode");
+            mp_raise_ValueError("bad compile mode");
     }
 
     mp_obj_code_t *code = m_new_obj(mp_obj_code_t);