Move the record block_padding capability fully into the record layer

Move the record block_padding capability fully into the record layer

Previously we were referencing the block_padding value through the
SSL_CONNECTION. Now it is held within OSSL_RECORD_LAYER.

Reviewed-by: Hugo Landau <hlandau@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/19198)