drivers/i2c/designware: translate return type in dw_i2c_dev_transfer

dw_i2c_transfer returns an enum cb_err type, but dw_i2c_dev_transfer
returns an int, so explicitly translate between the types. Since
dw_i2c_transfer only returns either CB_SUCCESS or CB_ERR which are
defined as 0 and -1, this won't change behavior of dw_i2c_dev_transfer.

Signed-off-by: Felix Held <felix-coreboot@felixheld.de>
Change-Id: Iaf2cbcf6564035d5c0fc13f5d5e7ac0d0425e85d
Reviewed-on: https://review.coreboot.org/c/coreboot/+/70831
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Fred Reitberger <reitbergerfred@gmail.com>
Reviewed-by: Eric Lai <eric_lai@quanta.corp-partner.google.com>
diff --git a/src/drivers/i2c/designware/dw_i2c.c b/src/drivers/i2c/designware/dw_i2c.c
index a080367..3bcb51a 100644
--- a/src/drivers/i2c/designware/dw_i2c.c
+++ b/src/drivers/i2c/designware/dw_i2c.c
@@ -862,7 +862,7 @@
 		printk(BIOS_ERR, "Invalid I2C bus number.\n");
 		return -1;
 	}
-	return dw_i2c_transfer(bus, msg, count);
+	return dw_i2c_transfer(bus, msg, count) == CB_SUCCESS ? 0 : -1;
 }
 
 const struct i2c_bus_operations dw_i2c_bus_ops = {