ch_ktls: Remove redundant variable result

Variable result is being assigned a value from a calculation
however the variable is never read, so this redundant variable
can be removed.

Cleans up the following clang-analyzer warning:

drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c:1488:2:
warning: Value stored to 'pos' is never read
[clang-analyzer-deadcode.DeadStores].

drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c:876:3:
warning: Value stored to 'pos' is never read
[clang-analyzer-deadcode.DeadStores].

drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c:36:3:
warning: Value stored to 'start' is never read
[clang-analyzer-deadcode.DeadStores].

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>