staging: r8188eu: use proper type for second argiment of rtw_(aes|tkip|wep)_(decrypt|encrypt)

rtw_aes_decrypt, rtw_tkip_decrypt, rtw_wep_decrypt, rtw_aes_encrypt,
rtw_tkip_encrypt, rtw_wep_encrypt are takes (u8 *) second argiment and
always uses it as (struct recv_frame *) or (struct xmit_frame *).
This is causes a lot of unnecessary type casts
and complicates refactoring.

Signed-off-by: Ivan Safonov <insafonov@gmail.com>
Link: https://lore.kernel.org/r/20200726210246.68633-1-insafonov@gmail.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>