arc: arcv1: Disable master/slave check

ARCompact cores are not supposed to be used in SMP designs
(this doesn't stop people from creation of heterogeneous chips,
for an example keep reading) so there's no point in
checking ARCNUM and halting somebody if we build for ARC700.

Moreover on AXS101 board we have ARC770 in the ASIC together with
other ARC cores and ARC770 happens to be the last node in JTAG chain
with ARCNUM = 4. And existing check halts the one and only core we
want keep running.

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>