flash_ec: support "--read" and "--verify" flags for npcx_uut
flash_ec: support "--read" and "--verify" flags for npcx_uut

This patch enables flash_ec to read EC image from npcx_uut type chip,
and to verify the flash programmed image.

BUG=b:133265593
BRANCH=none
TEST=manually ran flash_ec on fleex and careena.

flash_ec --board flex --image ${IMG} --verify
flash_ec --board flex --read ${TMP_IMG}

flash_ec --board careena --image ${IMG} --verify
flash_ec --board careena --read ${TMP_IMG}

Cq-Depend: chromium:1748803
Change-Id: Ifaefa64b0efed6c875c99ede59a3a1e0dfe0bf7f
Signed-off-by: Namyoon Woo <e8732cefb861f07768f47df788a8e8eb75efc09a@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/1749554
Reviewed-by: CH Lin <49997681dc186e71092740314bf6c6feeca6e227@nuvoton.com>
Reviewed-by: Raul E Rangel <9a9c998e11a2655b1de9a05eeeef5f710c0dc7ed@chromium.org>

coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec