[][SBC][Refactor mkits.sh related patches]

[Description]
Refactor mkits.sh related patches

- patch 'mtk-openwrt-feed/openwrt_patches-21.02/9990-fit-replace-@-with--.patch' first

- split mkits.sh related in
  'mtk-openwrt-feed/openwrt_patches-21.02/9989-sbc-secure-boot-and-anti-rollback-support.patch'
  to 'mtk-openwrt-feed/openwrt_patches-21.02/9991-fit-secure-boot-and-anti-rollback-support.patch',
  and move it to 'autobuild/openwrt_patches-21.02/0902-sbc-secure-boot-and-anti-rollback-support.patch'

[Release-log]
N/A

Change-Id: Id97d51c885d0e8f82de09f7380097f30261fcb52
Reviewed-on: https://gerrit.mediatek.inc/c/openwrt/feeds/mtk_openwrt_feeds/+/5806065
3 files changed