snow: Add support for EC based recovery.

Implement the get_recovery_mode_switch function using the newly added I2C
based Chrome EC support.

Change-Id: I9d0200629887f202edf017cba3222a7d7f5b053e
Signed-off-by: Gabe Black <gabeblack@chromium.org>
Reviewed-on: http://review.coreboot.org/3092
Reviewed-by: David Hendricks <dhendrix@chromium.org>
Tested-by: build bot (Jenkins)
1 file changed