drivers: crypto: Add support for STM32L4 AES accelerator

This patch completes the addition of support for the STM32L4 AES
accelerator by introducing conditional handling for different STM32 AES
HAL variants. Key changes include:

- Created device tree bindings `st,stm32l4-aes` for STM32L4 AES
- Replaced `copy_reverse_words` with `copy_words_adjust_endianness`
to handle endianness conversion for different variants.

Signed-off-by: Lucas Dietrich <ld.adecy@gmail.com>