Add the missing license header to drivers/mmc/core/block.c
Signed-off-by: Aviral Gupta <shiv14112001@gmail.com>
Link: https://lore.kernel.org/r/20210523155914.5200-1-shiv14112001@gmail.comSigned-off-by: Ulf Hansson <ulf.hansson@linaro.org>