mmc_add_host() may return error, if we ignore its return value, the memory
that allocated in mmc_alloc_host() will be leaked and it will lead a kernel
crash because of deleting not added device in the remove path.

So fix this by checking the return value and goto error path which will call
mmc_free_host(), besides, the timer added before mmc_add_host() needs be del.

And this patch fixes another missing call mmc_free_host() if usb_control_msg()
fails.

Fixes: 88095e7b ("mmc: Add new VUB300 USB-to-SD/SDIO/MMC driver")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20221101063023.1664968-9-yangyingliang@huawei.comSigned-off-by: Ulf Hansson <ulf.hansson@linaro.org>