base-files: Fix dhcp client disabling

Looks like there is new code path where dhcp client is set on wan, so
disabling it.
8 jobs for hotfix/dhcp in 21 minutes and 53 seconds (queued for 5 seconds)
Status Job ID Name Coverage
  Build
passed lists_generate #512663

00:00:57

passed medkit_mox #512660

00:21:52

passed medkit_omnia #512661

00:19:43

passed medkit_turris1x #512662

00:12:10

passed prepare_mox #512657

00:04:02

passed prepare_omnia #512658

00:04:09

passed prepare_turris1x #512659

00:04:01

 
  Verify
passed lists_verify #512664

00:01:54