depthcharge: correct SD controller base clock frequency

Added clock_base which saves base clock frequency read out from
CAP register. So frequency divider can be calculated correctly.
This also fixes min and max SD clock settings for their intended
purpose.

BUG=chrome-os-partner:42065
BRANCH=None
TEST=Built and booted glados from SD card.

Change-Id: I81ceed89f59b4a79976d5da594b3780fb379b6cb
Signed-off-by: Wenkai Du <wenkai.du@intel.com>
Reviewed-on: https://chromium-review.googlesource.com/290419
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Commit-Queue: Duncan Laurie <dlaurie@chromium.org>
Tested-by: Duncan Laurie <dlaurie@chromium.org>
2 files changed