UPSTREAM: VERSION: Change name pattern to match tag name from now on

This patch updated the VERSION file itself, and the document on
release process.

(cherry picked from commit 339a7dcd37f21f3421282880b315c0010f0e9ce7)

Original-Change-Id: I2bd2e57e42c29ea5a9d8bc334b86c6fa5c4b46a4
Original-Signed-off-by: Anastasia Klimchuk <aklm@flashrom.org>
Original-Reviewed-on: https://review.coreboot.org/c/flashrom/+/84811
Original-Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Original-Reviewed-by: Peter Marheine <pmarheine@chromium.org>
GitOrigin-RevId: 339a7dcd37f21f3421282880b315c0010f0e9ce7
Cr-Build-Id: 8732478032545050065
Cr-Build-Url: https://cr-buildbucket.appspot.com/build/8732478032545050065
Copybot-Job-Name: flashrom-main-copybot-downstream
Change-Id: Ic4e0d1c0f05748d5d746e7048c81ae994f3d34f5
Signed-off-by: chromeos-ci-prod <chromeos-ci-prod@chromeos-bot.iam.gserviceaccount.com>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/flashrom/+/5964937
Reviewed-by: Hsuan Ting Chen <roccochen@chromium.org>
Commit-Queue: Hsuan Ting Chen <roccochen@chromium.org>