tcl/target: Add XLP3xx configuration files

The patch adds configuration files for the following XLP 300-series
processors: XLP304, XLP308, XLP316.

Change-Id: Iaf2b807abf9fc4d7b51222fd40bdb18c6aca7d9c
Signed-off-by: Aleksey Kuleshov <rndfax@yandex.ru>
Signed-off-by: Peter Mamonov <pmamonov@gmail.com>
CC: Antony Pavlov <antonynpavlov@gmail.com>
CC: Dongxue Zhang <elta.era@gmail.com>
CC: Oleksij Rempel <linux@rempel-privat.de>
CC: Paul Fertser <fercerpav@gmail.com>
CC: Salvador Arroyo <sarroyofdez@yahoo.es>
CC: Spencer Oliver <spen@spen-soft.co.uk>
Reviewed-on: https://review.openocd.org/c/openocd/+/2323


Tested-by: jenkins
Reviewed-by: Oleksij Rempel <linux@rempel-privat.de>
Reviewed-by: Antonio Borneo <borneo.antonio@gmail.com>