Accroding to datasheet, feedback divider register high value is only
4 bit, it currently uses 5 bit, so correct it.
Change-Id: I1fe9fc076b712f27407c5f2735b15e64fb55e72e
Signed-off-by: Lin Huang <hl@rock-chips.com>
Reviewed-on: https://review.coreboot.org/22478
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Julius Werner <jwerner@chromium.org>