Bluetooth: Controller: Handle overlapping buffers on ull_adv{.c,_aux.c}

* Setting the adv data, scan rsp and adv aux ad data can happen on
overlapping buffers
* There can be other memcpy's that need to be changed to memmove but
these are the only ones I could reproduce the issue and since memmove
has a performance penalty, I left the others as is.

Signed-off-by: Yago Fontoura do Rosario <yafo@demant.com>