wlcore: don't allocate platform_data for platform device

The memory is managed by the platform device which takes ownership of it
when platform_device_add_data() is called. Our memory is simply leaked.

Signed-off-by: Arik Nemtsov <arik@wizery.com>
wclore: del platform data correctly on remove (squash)

A fix for the DT enabling patch - the pdev_data pointer does not
belong to us and is freed when the device is released. Dereference
to our private data first.

Signed-off-by: Arik Nemtsov <arik@wizery.com>