mmc: sdhci: Fix host->cmd is null

When data crc occurs, the kernel will panic because host->cmd is null.

Signed-off-by: Wenchao Chen <wenchao.chen@unisoc.com>

Fixes: efe8f5c9

 ("mmc: sdhci: Capture eMMC and SD card errors")
Cc: stable@vger.kernel.org
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Link: https://lore.kernel.org/r/20220907035847.13783-1-wenchao.chen666@gmail.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>