commonlib/storage: Zero extend MMC capacity

Fix CID 1376472 detected by coverity.  Zero extend the capacity instead
of sign extending it.

TEST=Build and run on reef

Change-Id: I6aac422fb1dacb75e0cc44a94ff1f467ce9f529e
Signed-off-by: Lee Leahy <Leroy.P.Leahy@intel.com>
Reviewed-on: https://review.coreboot.org/20392
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Martin Roth <martinroth@google.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>

0 files changed, 0 insertions, 0 deletions