The Saleae Logic is a logic analyzer designed to only receive logic signals. I believe the Saleae software can decode JTAG, but this does not allow it to program something or perform a boundary scan. JTAG is a two-way protocol requiring both inputs and outputs. While it may be possible to use the Saleae Logic as a JTAG dongle with a custom firmware, this is not something that is built in either the Saleae or OpenOCD software, and I am not aware of such a project. There are various cheap JTAG dongles available, for example the FT2232 based ones and Versaloon, that should work out of the box with OpenOCD.