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 v5.15.86 by commit 0959cc1685eb19774300d43ef25e318b457b156b, it was introduced in version v2.6.31 by commit f0bf7f61b8405224bc52fc9a3ccd167a68126e00. For more details please see the references link.