soc/intel/quark: Add SD/MMC test support

The SD/MMC test support consists of:

* Add Kconfig value to enable the SD/MMC test support.
* Add Kconfig value to enable the logging support.
* Add SD/MMC controller init code and read block 0 from each partition.
* Add logging code to snapshot the transactions with the SD/MMC device.
* Add eMMC driver for ramstage to call test code.
* Add romstage code to call test code.
* Add bootblock code to call test code.

TEST=Build and run on Galileo Gen2

Change-Id: I72785f0dcd466c05c1385cef166731219b583551
Signed-off-by: Lee Leahy <leroy.p.leahy@intel.com>
Reviewed-on: https://review.coreboot.org/19211
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Martin Roth <martinroth@google.com>
8 files changed