mmc: sdhci-s3c: drop unneeded MODULE_ALIAS

The MODULE_DEVICE_TABLE already creates proper alias for platform
driver.  Having another MODULE_ALIAS causes the alias to be duplicated.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Reviewed-by: Jaehoon Chung <jh80.chung@samsunhg.com>
Link: https://lore.kernel.org/r/20210916170511.137915-1-krzysztof.kozlowski@canonical.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>