crypto: chtls - remove set but not used variable 'csk'

Fixes gcc '-Wunused-but-set-variable' warning:

drivers/crypto/chelsio/chtls/chtls_cm.c: In function 'chtls_disconnect':
drivers/crypto/chelsio/chtls/chtls_cm.c:408:21: warning:
 variable 'csk' set but not used [-Wunused-but-set-variable]

drivers/crypto/chelsio/chtls/chtls_cm.c: In function 'chtls_recv_sock':
drivers/crypto/chelsio/chtls/chtls_cm.c:1016:23: warning:
 variable 'tcph' set but not used [-Wunused-but-set-variable]

'csk' and 'tcph' are never used since introduce
in commit cc35c88a

 ("crypto : chtls - CPL handler definition")

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>