Move MAC removal responsibility to the various protocol "enc" functions

Move MAC removal responsibility to the various protocol "enc" functions

For CBC ciphersuites using Mac-then-encrypt we have to be careful about
removing the MAC from the record in constant time. Currently that happens
immediately before MAC verification. Instead we move this responsibility
to the various protocol "enc" functions so that MAC removal is handled at
the same time as padding removal.

Reviewed-by: Shane Lontis <shane.lontis@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/12288)