netifd: Update to latest OpenWrt 21.02 merge
Set netifd to latest version which includes a merge of new commits from OpenWrt 21.02. Regression tests have been run without any issues.
In commit f87b0bdc (Merge branch 'openwrt-21.02' (from main OpenWrt repo) into devel (in IOPSYSWRT feed openwrt_core repo), 2021-08-13) we inadvertently set netifd to an incorrect version without IOPSYSWRT changes for BCM platforms, which is why it had been changed back to the previous version in d7b54b97 (netifd: Revert update from merge, 2021-08-16). Fix things now for real by setting it to the correct revision.
Fixes: f87b0bdc (Merge branch 'openwrt-21.02' (from main OpenWrt repo) into devel (in IOPSYSWRT feed openwrt_core repo), 2021-08-13)