mmc: moxart: 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 f0502fe86a2db2336c9498d2de3e97f22dcf85ae, it was introduced in version v3.16 by commit 1b66e94e6b9995323190f31c51d8e1a6f516627e. For more details please see the references link.