crypto/chtls:Fix compile error when CONFIG_IPV6 is disabled

Fix compile errors,warnings when CONFIG_IPV6 is disabled and
inconsistent indenting.

v1->v2:
- Corrected errors/warnings reported when used newer gcc version,
  unused array.

Fixes: 6abde0b2 ("crypto/chtls: IPv6 support for inline TLS")
Signed-off-by: Vinay Kumar Yadav <vinay.yadav@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>