platform/chrome: cros_ec_typec: Check for EC driver

The EC driver may not be initialized when cros_typec_probe is called,
particulary when CONFIG_CROS_EC_CHARDEV=m.

Signed-off-by: Akihiko Odaki <[e-mail]>
Reviewed-by: Guenter Roeck <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Prashant Malani <[e-mail]>

drivers/platform/chrome/cros_ec_typec.c

···
 	}
 
 	ec_dev = dev_get_drvdata(&typec->ec->ec->dev);
+	if (!ec_dev)
+		return -EPROBE_DEFER;
+
 	typec->typec_cmd_supported = cros_ec_check_features(ec_dev, EC_FEATURE_TYPEC_CMD);
 	typec->needs_mux_ack = cros_ec_check_features(ec_dev, EC_FEATURE_TYPEC_MUX_REQUIRE_AP_ACK);