mmc: core: Do not export MMC_NAME= and MODALIAS=mmc:block for SDIO cards

SDIO non-combo cards are not handled by mmc_block driver and do not have
accessible CID register which is used for MMC_NAME= construction.

Signed-off-by: Pali Rohár <pali@kernel.org>
Reviewed-by: Marek Behún <marek.behun@nic.cz>
Link: https://lore.kernel.org/r/20200527110858.17504-1-pali@kernel.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>