Apply changes of merge openwrt/openwrt-21.02 into devel

This is a commit that applies the changes corresponding to the merge
   cd81ce00c4 (Merge branch 'openwrt/openwrt-21.02' into devel, 2021-07-15)
in the main IOPSYSWRT repo to the iopsys-ramips-target in the
feeds/targets repo.

Changes have been done by applying the diff between
  bbbc01ede5 (uclient: update to Git version 2021-05-14, 2021-05-14)
and
  f3f70fb956 (netifd: update to the latest version, 2021-07-14)
of the target/linux/ramips/ directory in the main IOPSYSWRT repo to the
iopsys-ramips directory in this (feeds/targets) repo.