mmc: core: Export device/vendor ids from Common CIS for SDIO cards

Device/vendor ids from Common CIS (Card Information Structure) may be
different as device/vendor ids from CIS on particular SDIO function.

Kernel currently exports only device/vendor ids from SDIO functions and not
"main" device/vendor ids from Common CIS.

This patch exports "main" device/vendor ids for SDIO and SD combo cards at
top level mmc device in sysfs hierarchy.

Userspace can use e.g. udev rules to correctly match whole SDIO card based
on Common CIS device/vendor id and not only one particular SDIO function.
Having this information in userspace also helps developers to debug whole
SDIO card as e.g. kernel mmc quirks use device/vendor ids from Common CIS
and not from particular SDIO function. Also it allows to write userspace
applications which list all connected SDIO cards based on CIS ids.

Signed-off-by: Pali Rohár <pali@kernel.org>
Reviewed-by: Marek Behún <marek.behun@nic.cz>

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Changes in V2:
* Make sd_std_group static
* Put more information into commit message
3 files changed