Provide jtagspi with specific procedures to be able to use jtagspi for programming spi-flash devices on lattice certus and certus po devices. Change-Id: I6a8ec16be78f86073a4ef5302f6241185b08e1c6 Signed-off-by: Daniel Anselmi <danselmi@gmx.ch> Reviewed-on: https://review.openocd.org/c/openocd/+/7825 Tested-by: jenkins Reviewed-by: Antonio Borneo <borneo.antonio@gmail.com>