cxgb4/ch_ktls: decrypted bit is not enough

If skb has retransmit data starting before start marker, e.g. ccs,
decrypted bit won't be set for that, and if it has some data to
encrypt, then it must be given to crypto ULD. So in place of
decrypted, check if socket is tls offloaded. Also, unless skb has
some data to encrypt, no need to give it for tls offload handling.

v2->v3:
- Removed ifdef.

Fixes: 5a4b9fe7 ("cxgb4/chcr: complete record tx handling")
Signed-off-by: Rohit Maheshwari <rohitm@chelsio.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>