Bluetooth: EWS: handling different Control fields

There are three different Control Field formats: the Standard Control
Field, the Enhanced Control Field, and the Extended Control Field.
Patch adds function to handle all those fields seamlessly.

Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>