wifi-scripts: fix wifi failure on specifying value of DAE client

wifi-scripts: fix wifi failure on specifying value of DAE client

The code to be replaced is a glorious no-op. A default value for
config.radius_das_client does not need to be assigned. This parameter
already has non-empty value: see the enclosing 'if' block.

As a result, the value of config.radius_das_client never gets modified
to contain both dae_client and dae_secret. This breaks hostapd.add_iface()
that expects config.radius_das_client to contain both dae_client and
dae_secret separated by a whitespace.

Fixes: #21519
Signed-off-by: Val Kulkov <val.kulkov@gmail.com>
Link: https://github.com/openwrt/openwrt/pull/21522
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
(cherry picked from commit c7f585bfc3dcd6da0d13ffdee5fa8ac47224004a)