i2c: ljca: Remove unused "target_addr" parameter

The stop command doesn't use any address on the target:

  w_packet->data[0] = 0;

and indeed the targed_addr parameter was unused. Remove it.

Cc: Wentong Wu <wentong.wu@intel.com>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>