Update baremetal dejagnu boards

Make changes to baremetal boards definition:
* nSIM: Do reload on run each time, that fixes some tests
* Hardware watchpoint are not available on both simulators.

Signed-off-by: Anton Kolesov <akolesov@synopsys.com>
(cherry picked from commit e392dc3d80f42994bfd45a637aafe95e0e30aabf)
Avoid repeated reboots of nsim_gdb

nSIM outputs messages to std(out|err) as it accepts new connections. This
output is ignored is by this script, however it seems that buffer that contains
output at some points stops dropping old output to make a place for new one and
simply overflows.  Thus sim_gdb cannot write to stream, it is blocked and it
stops responding to TCP connection and Dejagnu is forced to restart it. I don't
know a way to redirect nsim_gdb output to null from Expect, so we have to use a
shell to help as here.

Signed-off-by: Anton Kolesov <Anton.Kolesov@synopsys.com>
(cherry picked from commit f49ee2da2b68360828c5eb48f33dffa4764f8d90)
Support Git 1.8

arc-versions.sh script was failing during tag checkout because Git 1.8 has
different output than previous versions. This patch adds support for it.

Signed-off-by: Anton Kolesov <Anton.Kolesov@synopsys.com>
(cherry picked from commit 1b76518761496fbf5a198a45194e84d4cdc0c1c2)