drivers: crypto: smartbond: Crypto Driver Update

This commit should fix the followings:
1. Suppress compiler warnings
2. Cryptographic mode should first be exercised before
   applying the secure key
3. In-memory word swap operations should be omitted as
   the key should reside in the flash memory and so any
   write access should raise a busfault exception

Signed-off-by: Ioannis Karachalios <ioannis.karachalios.px@renesas.com>