chameleon: update FPGA boot documentation

Update parameter order in documentation, fix broken link to image.

BUG=b:169057055
TEST=n/a

Cq-Depend: chromium:2533124
Change-Id: Iccf559df52420405b272cbd97bb59998ec1657d5
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/zephyr-chrome/+/2537908
Tested-by: Paul Fagerburg <pfagerburg@chromium.org>
Auto-Submit: Paul Fagerburg <pfagerburg@chromium.org>
Reviewed-by: Jack Rosenthal <jrosenth@chromium.org>
Commit-Queue: Jack Rosenthal <jrosenth@chromium.org>
1 file changed