mmc: via-sdmmc: fix return value check of mmcaddhost()
This is an automated ID intended to aid in discovery of potential security vulnerabilities. The actual impact and attack plausibility have not yet been proven. This ID is fixed in Linux Kernel version v4.9.337 by commit 076bcd2c93e16b05c10564e299d6e5d26a766d00, it was introduced in version v2.6.31 by commit f0bf7f61b8405224bc52fc9a3ccd167a68126e00. For more details please see the references link.