automation: update xilinx test scripts (tty)

automation: update xilinx test scripts (tty)

Update serial device names from ttyUSB* to test board specific names.

Update xilinx-smoke-dom0-x86_64 with new Xen command line console options,
which are now set as Gitlab CI/CD variables. Abstract the directory where
binaries are stored. Increase the timeout to match new setup.

Signed-off-by: Victor Lira <victorm.lira@amd.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
(cherry picked from commit 95764a0817a51741b7ffb1f78cba2a19b08ab2d1)